210

REPORT ON ZOOLOGY, MDCCCXLII1.

gularis ( L. quadrangularis, Mull.); and a new species, A. reticulata. (7)Pleuroxus: anterior margin prominent on the upper portion; the lower parttruncated, or out off straight, first pair of feet very large: PI. trigonellus(L. trig., Mull.), and PI. hamaius ( L. ham., Baird.) (8) Perucantha: oval,the lower extremity of the shell slightly curved backwards, and, as well asthe upper extremity of the anterior margin, beset with strong, hookedspines : P. truncata (L. truncata, Mull.)

Ostracoda . —A Cypris was brought by Dieffenbaeh from New Zealand (Travels, ii, p. 268), and has been described by Baird: C. nova Zelandice;egg-shaped, elongated, equally rounded at each end, somewhat inflatedand with a shallow sinus in the middle of the anterior margin, smooth,shining, entirely without hairs; resembling G. detecta, Mull., in which, how-ever, the shell is not inflated.

Copepoda. —Philippi (Arcliiv. 1843, i, p. 54) has communicated hisfurther observations on the Copepoda of the Mediterranean. A memoir, ofimportance in the systematic arrangement of the order. Seven new generaare instituted: Puchceta, Idya, Metis , AEnippe, Onccea, Puryte, Idomene, eachwith a new species. Cyclopsina, Edw., is limited by the author to C. castor,and C. staphylinus and furcatus are referred to Nauplius, of which genus hementions 14 species.

Goodsir (Edinb. New Philosoph . Journ. vol. xxxv, p. 336, pi. 6) hasdescribed a new species of Cetochilus, differing from C. australis in havingtwo long spines on the twenty-second and twenty-third joints of the externalantennae, and also in the form of the foot-jaws, and which the author callsC. septentrionalis; besides this (ib. p. 337) a new genus, Irenaus, with thefollowing characters: a large tubular organ arising from the abdominalsurface of the body, bears at the apex the visual organs ; the right antenn®much swollen a little behind the middle; 10 jaw-feet. The species I. splen-didus is remarkable from the metallic brilliancy of the colours, in whichsappharine and emerald predominate. Both are found in the “ Maidre” (vid.supra), in the Firth of Forth , the latter solitary, the Cetochilus in masses.

Siphonostoma, —Importantand more precise investigations on some speciesbelonging to the North Sea have been instituted by Rathke (Verhandl. d. Kais.Leop. Akad.xii,p.98.) The species observed wer e,Caligus curtus, C.diaphanus,Nordm., C. hippoglossi, Kroy., Nicothoe Astaci., Aud., Chondracanthuslophii (gibbosus, Kroy), Lerncea brachialis, L. The internal structure ofCaligus curtus, Nicothoe Astaci. Chondracanthus Lophii, Lerncea brachialis, hasbeen investigated. Especially important are the observations on the develop-ment of Nicothoe Astaci ; for in this species no metamorphosis takes place,as is elsewhere the case in this order, but the young leave the egg in a formsimilar to that which is presented by the adult animals. Only the largewing-shaped processes of the cephalo-thorax of the female are wanting;these contain the sexual organs, and are consequently developed at a later