segmentis ventralibus lateraliter punctatis, medio vix punctatis ; lamina subgenitali conspicua, lævi, politissima, convexa. Femoribus anticis muticis. Larvis totis aterrimis. Long. corporis ♂ 37-45, 943 millim.; pronoti ♂ 10-13, 9 103; pronoti lat. ♂ 14-17, 16; long. tegminum ♂ 29-53, 29. Hab. Numerous adult and immature specimens of both sexes from the Nágá hills (J. Butler and Godwin-Austen), Brahmaputra valley (A. W. Chennell), and Dikrang valley (Godwin-Austen). Panesthia Saussurii, n. sp. 2. P. mandarinea, Saussure, Mélanges Orthopt. p. 100, pl. 3. fig. 23, non p. 40, pl. 1. fig. 25. I have recently received from Johore in the Malay peninsula a fine series of specimens of P. mandarinea, none of which exhibit the least approach to the remarkable structure of the abdomen seen in the insect described and figured by De Saussure as the supposed female of it. The larvae of P. mandarinea, moreover, are jet-black throughout, while those of P. Saussurii are deep black-brown symmetrically variegated with pale testaceous on every part of the body, including the legs, which are ringed, the antennæ, which are tipped, and the head, which is triply banded, with the same colour. A further reason for refusing to accept the insect figured by De Saussure on pl. 3 (op. supra cit.) as the female of the one represented on pl. 1 is that the latter is itself also a female, the sides of the pronotum in the true males of which are produced into huge curved horns, each separated from the broad semioval median lobe covering the head by a deep rounded emargination. Hab. A single specimen of the male from Sikkim (L. Mandelli). This insect having been captured just prior to the last moult, the organs of flight are still in rudiment, and the pronotum is still nonemarginate. Journ. Asiatic Soc. Beng. vol. xlv. part 2, 1876. On some Facts relating to the Nutrition of the Embryo in the My investigations in experimental teratogeny have enabled me to ascertain some facts with regard to the nutrition of the embryo in the egg. If in the first days of incubation we remove the blastoderm with the portion of the vitelline membrane that covers it, and the layer of albumen lining this section of the vitelline membrane, and then, after separating the blastoderm from the vitelline membrane, coagulate the albumen by means of alcohol or hot water, we find that the albumen has completely disappeared above the embryo. There is here a vacant space in the form of a hollow cylinder, or rather a portion of a cone with a circular base. This perforation of the albumen is the more considerable in proportion to the distance from the commencement of incubation, and consequently to the space occupied by the embryo in the blastoderm. This fact was observed by Agassiz; but I have been able to go further than that illustrious naturalist. In fact I have ascertained that this disappearance of the albumen is connected solely with the development of the embryo and of the vascular lamella, which, in its origin, is not distinguished from the embryo itself. The albumen disappears only above the circle formed by the vascular area; and its disappearance increases like this circle. If by chance, as I have observed in my experiments, the vascular area presents an elliptical form, the empty space produced by the disappearance of the albumen presents the form of an elliptical cylinder, or, more correctly, of a portion of a cone with an elliptical base. Thus during the early part of the development the formation of the vascular area is connected with the gradual disappearance of the layer of albumen corresponding to it on the other side of the vitelline membrane. On the contrary, nothing of the kind takes place in all that portion of the blastoderm which is beyond the vascular lamella and surrounds it. This led me to think that the albumen necessary for the nutrition of the embryo does not assist in the nutrition of the blastoderm itself. I have verified this prevision by the examination of blastoderms which had developed without producing any embryo, and which nevertheless had covered almost the whole surface of the yelk. This fact I have several times observed in the course of my teratogenical studies. Under these circumstances the albumen forms a perfectly continuous layer above the blastoderm. We must therefore assume that the blastoderm derives its elements from the yelk, whilst at the commencement of incubation, and, at least, up to the period of the complete closure of the amnios, the embryo is developed at the expense of the albumen. I may add that the ascertainment of the disappearance of the albumen is the process that I adopt in my investigations whenever I wish to know whether an embryo is being developed in an egg, a fact which the death and disorganization of the blastoderm do not always allow to be ascertained directly. There are, in fact, many circumstances under which the embryo perishes very early, quite at the commencement of the development; and if the egg is not opened until after the lapse of some days, it is often very difficult to find any appreciable traces of its existence. The disappearance or the preservation of the albumen furnishes a sure means of deciding as to the former existence of an embryo, and to decide whether the blastoderm has produced an embryo or whether it is one of those blastoderms without an embryo, the occurrence of which in my experiments I have just mentioned.-Comptes Rendus, Oct. 30, 1876, p. 836. On the Structure and Organization of the Polyphemida. By Dr. C. CLAUS. The structure of the body and limbs of the Polyphemide (Bythotrephes, Polyphemus, Podon, Evadne) may be referred in detail to the well-known structure of the Daphnidæ, and their peculiarities thus completely explained morphologically. The principal difference which leads physiologically to new conditions of embryonic nourishment, and is also of importance with regard to the external form of the body, consists in the transformation of the brood-chamber, bounded by the skin of the back and the inferior lamella of the shell, into a uterus-like sac, the cellular wall of which (hypodermis) becomes a nutrient organ of the ova and embryos, either throughout its whole extent (Podon, Evadne), or only in the ventral lamella, which is in contact with the intestine. The nervous system could be traced in its whole course in all four genera. The brain is followed by a subœsophageal ganglion, which is united to it by short broad œsophageal commissures, and by the ventral ganglionic chain, the four inflations of which, united by transverse commissures, emit nerves for the limbs. The last and smallest pair of ganglia also sends forth nerves to the abdomen and to the tactile setæ of the postabdomen. The crystalline cones of the large movable eye consist throughout of five segments; the nervous rods belonging to them show lamellar structure. The shell-gland was traced in all the genera in its whole length to its orifice. In its course it presents characteristic peculiarities in each genus and species, but consists throughout of the ampulliform sac, the inner and outer looped canal, the terminal duct, and the short narrow efferent tube. The dilated terminal duct, extended after the fashion of a reservoir, contains large shining urinary coucretions in Podon and Evadne. The adherent organ of Evadne and Podon is not a sucking-cup with radiating muscles, but an excretory organ composed of large glandular cells with streaky protoplasm. In Evadne nine or ten cells are usually employed in its formation; their conically decreased secreting ends are applied to the well-known cuticular disk. The ova, as in the Daphnidæ, are produced in four-celled chambers of the ovary, but are extraordinarily small when they pass into the brood-chamber, where an abundant supply of nourishment is furnished to the developing embryo by secretion from the walls. In Evadne the embryo becomes pregnant while still in the body of the mother, and is usually born with four ova in process of segmentation in the uterus. The formation of the winter egg in Evadne takes place by absorption-processes of the neighbouring egg-chamber.-Kais. Akad. der Wiss. in Wien, Oct. 26, 1876. On the Colydiidae of New Zealand. By D. SHARP. In the Annals,' July 1876, p. 22, I established a new genus of Colydiida, with the name Epistrophus. I find this word has already been used by Kirsch for a genus of Curculionidae; and I propose therefore for the genus of Colydiidæ above alluded to the name of Epistranus in place of Epistrophus. THE ANNALS AND MAGAZINE OF NATURAL HISTORY. [FOURTH SERIES.] No. 110. FEBRUARY 1877. IX. On two Vitreohexactinellid Sponges. [Plate IX.] THE following descriptions of Eurete farreopsis, n. sp., and Myliusia Grayi, Bk., respectively have been made more especially for two purposes, viz. the former to show the mode of growth in Farrea occa, which has not yet been described from a living specimen, and the latter to illustrate the only known living species possessing the structure of the Ventriculida that has come to notice. I am indebted to my friend Dr. J. Millar for the specimen of Eurete farreopsis, which has been whitened at the expense of the soft parts-for sale, not for the purposes of natural history,—and, from being very delicate in the last-formed portions, has been much broken. Nevertheless sufficient remains for description and for the accompanying illustration of the the general form, which has been taken from a photograph; while the elementary parts more particularly have been obtained from minute shreds of dried sarcode still left about the skeleton, in which are wrapt up the rosettes and smaller spicules of the species. The specimen of Myliusia Grayi, Bk., belongs to the British Museum; and through the obligingness of Dr. Günther I am enabled to give an illustration of this, also delineated from a photograph. It was taken alive, as the presence of the sarcode in many parts indicates; but, appearing very insignificant from its smallness, it has not received that treatment which its Ann. & Mag. N. Hist. Ser. 4. Vol. xix. 9 importance as the only living representative of the Ventriculidae in structure deserves; nevertheless with what remains of this also there is, as will be seen, abundance left for description and illustration. It has already been described and named by Dr. Bowerbank (Proc. Zool. Soc. May 13, 1869, p. 335, pl. xxv. fig. 1), who has given a most faithful illustration of its general structure, to which I would refer the reader; but as neither the general form of the specimen itself, including its elementary composition, has been illustrated, nor the resemblance of the latter to that of the Ventriculidæ pointed out, it seems to me that a more detailed record of this precious little sponge is desirable; and this I have endeavoured to supply. Eurete farreopsis, n. sp. (Pl. IX. figs. 1–7.) Vitreohexactinellid. Skeleton. General form bush-like, fixed, sessile, composed of many tubo-branches anastomosing clathrously. Colourless, translucent, becoming white from increasing density of structure towards the base. Branches short, thick, cylindrical, hollow, formed of a delicate thin reticulated wall thickening from the growing margin towards the base or oldest part, widely separate, dichotomous, anastomosing as before stated. Orifices of branches respectively circular at first (fig. 2, a), then expanded (fig. 2, b), afterwards funnel-shaped (fig. 2, c), becoming elliptical and contracted in the centre (fig. 2, d), where, by the union of the approximated parts of the margin, two circular orifices are formed which grow into two short, round, tubular branches in opposite directions (fig. e), to divide again after the same manner, and so on-or to anastomose with other neighbouring branches, when each branch still gives off two others, so that at the point of junction there are four branches instead of two. Where union takes place, either by the approximation of the two opposite parts of the margin or by direct anastomosis, a raphe is formed. General structure of the wall reticular, the longitudinal lines of fibre, which are the largest, remaining parallel while the tube is round (fig. 2, a), but radiating upon the same plane successively where the orifice becomes expanded (fig. 2, c, d). External surface rough, from the projection of the arms of sexradiate spicules which have not become enveloped by the vitreous fibre; internal surface still rougher from the same cause; mid structure or wall composed of sexradiate spicules woven into a reticulated tissue by the vitreous fibre, of which the meshes are subquadrangular, and, as before stated, the longitudinal fibres largest; varying in thickness from an extremely thin layer of minute sexradiate spicules in |