the ends of the vertical fibres appear to be most frequently arranged hexagonally, with one in the centre, thus presenting respectively six horizontal arms, which, together with the ascending and descending one, would make eight.

We have also to assume, in case of its having been a hexactinellid sponge, the transformation of siliceous into calcareous material,-not a usual occurrence; for there are no calcareous sponges with a hexactinellid structure; indeed they are all fibreless, that is, they consist respectively of a mass of sarcode densely charged with calcareous spicules, like a bag of pins-only, of course, with a definite arrangement. But, as I have just stated, the structure of this species, like that of all the rest of the Stromatopora, requires to be studied in all its bearings before a correct opinion can be obtained of its original

nature.

Thus, in recapitulation, we have seen the identity that exists between the recent species of Hydractinia and the fossil species of the Suffolk Crag and Upper Greensand of Haldon Hill, near Exeter, respectively; then the striking. resemblance between the chitinous tissue-fibre of the chitinous Hydractiniidæ, especially that of Chitina ericopsis, and the tissue-fibre of Parkeria, together with that of the radial tubes of the latter to the radiating or vertical tubes of Hydractinia pliocena; afterwards the resemblance of Parkeria to Loftusia. Then the resemblance of the Lower White Chalk fossil (? Bradya tergestina) to Parkeria on the one, and the Stromatopora on the other side; lastly, the presence in Stromatopora · striatella, of the Upper Silurian System, of a concamerated test in the centre, just as foreign to its structure as the concamerated test in Parkeria, which Stromatopora otherwise so intimately resembles.

All this chain of evidence seems to lead to the conclusion that the whole of these organisms, both recent and fossil, were species of Hydrozoa, and neither Foraminifera nor Sponges.

But foregone conclusions with so-called scientific men, are too often unfortunately like fashion in their governing power, since, although facts may be demonstrated, they are frequently negatived by individuals who, if they reflected, would, from their want of actual experience in this matter, be modest where they are violent in party denunciation. At the same time, as I have long since stated, "in proportion to the general acquaintance with the lower animals will be the correctness of the views respecting them, both recent and fossilized."

EXPLANATION OF PLATE VIII.

N.B. Figs. 1-6, 10, 12, 21, and 23 are on the scale of 1-48th to 1-1800th inch, fig. 9 on the scale of 1-96th to 1-1800th, and fig. 14 on the scale of 1-96th to 1-2700th inch; all the rest are of the natural size. It should be remembered that the ground-work of figs. 8, 11, 15, 16, 18, and 19 is granulated, but too small to be represented in a drawing of the natural size; hence the white ground must be considered as such; the granulation being produced by the weathering out of the interstitial matter of the tortuous anastomosing tissue-fibre of which the organisms respectively were composed. In figs. 20, 22, and 24, this granulation, of course, is not present, as they are taken from fresh sections. Fig. 1. Hydractinia echinata. Vertical section of skeleton, magnified; composed of chitinous tissue-fibre. a, primary lamina; b, primary interval; c, secondary lamina; d, secondary interval; e e, small spines, free and connected with the secondary lamina respectively; f, surface of third lamina and that of the Hydractinia; g, large spine.

Fig. 2. The same. Horizontal section of base of large spine: a, closed

summit of same.

Fig. 3. The same. Fragment of cœnosarcal stolon-like tubulation creeping over the surface, forming corresponding grooves in the latter and connected with the interior. a, annulation; b, the same, truncated to show the diaphragmatic form of the constrictions; c, points of chitine ("horn cells ") on the part sinking into the interior.

Fig. 4. Hydractinia calcarea, n. sp. Vertical section of skeleton, magnified; composition calcareous. a, primary lamina; b, primary interval; c, secondary or surface-lamina; d, small spines, free, and connected respectively with secondary lamina; e, spines on secondary or surface lamina; f, large spine; gg, chitinous diaphragms leading from the apertures on the surface (fig. 5, ccc) to the primary interval.

Fig. 5. The same. Diagram of portion of surface to show:-a a a, large spines; bbb, area of small spines, not delineated for perspicuity; ccc, apertures leading down through short tubes respectively into primary interval; ddd, interstitial fossæ, smooth, not spined; ee hole of the diaphagm as seen through the aperture. Fig. 6. The same. Horizontal section of base of large spine. a, form of columnar cavity; b, closed summit of large spine.

Fig. 7. Hydractinia pliocena, Allman, (fossil), natural size; vertical section. a a, Buccinum; bb, Hydractinia, showing the " intervals" in the form of chambers, arranged in horizontal lines, cut vertically by radiating tubes.

Fig. 8. The same. Portion of natural surface, natural size, showing:— a, large spines; bb, grooves formed by cœnosarcal tubulation (fig. 3); c, circular area, to which the apertures of the surface are added, all the rest having been omitted for perspicuity. Fig. 9. The same. Vertical section of fragment of surface of last-formed "lamina and intervals," magnified, showing how the vertical tubes on each side of the interval or chamber, being opposite, might appear in the general section to be continuous. a, small spines of natural surface; b, apertures in natural surface; c, annulated tubes leading down from apertures to intervals; ddd, chambers or intervals; e, spines remaining free in intervals.

Fig. 10. The same. Longitudinal section of a tube magnified, showing the "annulation;" a, tranverse section to show the diaphragmatic form of the constriction, with hole in the centre.

Fig. 11. Hydractinia Vicaryi, n. sp. (fossil), nat. size. Portion of natural surface, showing:-a, large spines; b, circular area, to which the apertures of the surface are added; all the rest having been omitted for perspicuity.

Fig. 12. The same. Cast of tube, showing annulations. a, cylindrical form of the cavity in which the cast (b) is found. Fig. 13. Parkeria sphærica. Vertical section, natural size.

a, infiltrated or consolidated zone or shell; b, semi-infiltrated zone; c, uninfiltrated portion, or kernel; d, the first six laminae of c, delineated to show intervals traversed vertically by the radiating tubes; the innermost elliptical, at one end of which the dark portion represents a cavity in which probably there was some kind of foreign body.

Fig. 14. The same. Diagram of tissue-fibre, magnified to show its reticulated, anastomosing, contorted arrangement and its composition. a, fibre, composed of colourless transparent calcspar; b, coating or incrustation, composed of granular, crystalline, yellowish calcite.

Fig. 15. The same. Diagram of portion of surface of kernel (fig. 13, c), showing:-a, ends of radiating pillars of tissue-fibre; b, circular

ral size.

area, to which the ends of the radiating tubes are added. NatuFig. 16. The same. Diagram of portion of natural surface of a specimen 13 inch in diameter, showing :-a, ends of radiating pillars of tissue-fibre; b, circular area, to which the ends of the radiating tubes are added. Natural size.

Fig. 17. The same. Vertical section, natural size. a, circle indicating size of specimen; b, the first six laminæ, delineated to show intervals traversed vertically by the radiating tubes; c, foreign nucleus, consisting of a fragment of a Nautiloid test.

Fig. 18. Loftusia persica, Brady. Portion of natural surface, natural size. a, papilliform apertural eminences of radial tubes; b, boss-like eminence, presenting, c, a trace of branched lines across (? radiating) from the summit.

Fig. 19. Stromatopora with bossed surface, in black-grey Devonian limestone. In the possession of Mr. Vicary. Portion of natural surface, natural size. aaa, bosses presenting the "stellate system of canals "respectively on the summit; b, papillary apertures of radial tubes.

Fig. 20. Stromatopora in grey Devonian limestone, subinfiltrated. In the possession of Mr. Vicary. Diagram of horizontal section, natural size. a, stellate systems of canals; b, ends of radiating tubes. Fig. 21. The same. Horizontal section of ends of radiating tubes, magnified, to show intertubular communication like that of Syringopora: a, longitudinal section of tube, to show diaphragmatic lines and appearance of annulation; b, intertubular communi

cations.

Fig. 22. Stromatopora (Syringopora), in grey Devonian limestone. In the possession of Mr. Vicary. Nearly horizontal section, natural size. a, stellate system of canals; b, ends of the radiating tubes, much larger than in the foregoing instance.

Fig. 23. The same. Section of radiating tube, magnified, to show the diaphragmatic lines of annulation cut obliquely.

Fig. 24. Stromatopora striatella, in yellowish compact limestone, from Upper Silurian system. Portion of natural surface, natural size. a, stellate systems of canals; b, papillary apertures of radial tubes. Fig. 25. The same. Horizontal section, natural size, showing:foreign nucleus, consisting of a fragment of a concamerated test like Orthoceras.

V.-Descriptions of twenty-five new Species of Hesperidæ. By W. C. HEWITSON.

WHEN ten years ago I described 176 new species of Hesperidæ, I stated that I would apologize for doing so (knowing the worthlessness of descriptions unaccompanied by illustrations) if I did not hope to figure the whole in the 'Exotic Butterflies.' I am happy to say that nearly the whole have been figured; and, though I cannot now make the same promise, since that work has come to its hundredth and final part, I still hope to figure the Hesperide which I am now describing in the 'Illustrations of Diurnal Lepidoptera,' in which the Lycanida now make their appearance. I may repeat now what I stated then, that, although numbers of Hesperide differ little on the upperside, some characteristic traits exist on the underside of the posterior wing; and upon these I have chiefly relied to enable me to discriminate one from another.

Hesperia Gonessa.

Alis utrinque fuscis: anticis punctis octo hyalinis: his infra angulo anali albo fasciaque submarginali pallida: posticis infra fasciis duabus macularum pallidarum: abdomine albo.

Upperside dark brown. Anterior wing with eight small transparent white spots-two in the cell, three in a longitudinal band below these, and three near the apex: the fringe of the posterior wing and the abdomen white.

Underside as above, except that the anal angle of the anterior wing is broadly white, and that there is a submarginal series of indistinct pale spots, and that the posterior wing has two submarginal series of similar spots.

Exp. 1 inch.

Hab. Angola (Rogers).

In the collection of W. C. Hewitson.

Hesperia Fiscella.

Alis utrinque fuscis: anticis punctis sex hyalinis: posticis fascia ochracea: his infra fascia flava.

Upperside dark brown.

Anterior wing with six transparent spots-one in the cell, one just below it, one (minute) between it and the inner margin, and three (at a distance from each other) between it and the apex. Posterior wing crossed transversely by an indistinct ochreous band.

Underside as above, except that the band of the posterior wing is more distinct and pale yellow.

Exp. 1 inch.

Hab. Para.

In the collection of W. C. Hewitson.

Hesperia Zema.

Alis utrinque rufo-fuscis: anticis punctis sex hyalinis: posticis macula ochracea: his infra fascia alba.

Upperside dark rufous-brown. Anterior wing with six transparent white spots-one in the cell, two divided by a branch of the median nervure, and three near the apex: a black linear spot (which denotes the male) from the inner margin. Posterior wing with an indistinct central ochreous spot: the fringe white.

Underside as above, except that it is rufous, that the anterior wing has the costal margin and a subapical band ochraceous, and that the posterior wing is crossed from the costal margin to the submedian nervure by a band of pale yellow. Exp. 1 inch.

Hab. Darjeeling and Sarawak.

In the collection of W. C. Hewitson.

Hesperia Zimra.

Alis supra fuscis: anticis fascia longitudinali media punctisque duobus subapicalibus bifidis hyalinis: posticis fascia angulari ochracea: his infra viridi-fuscis, macula basali fasciaque lata flavo-albis.

Upperside dark rufous-brown. Anterior wing crossed longitudinally at the middle by a quadrifid band, and near the apex by two bifid spots, all transparent. Posterior wing crossed transversely near the middle by an angular ochreous band: the fringe pale yellow.

Underside as above, except that it is tinted with green, that both wings have a submarginal band of ochreous spots,