ANATOMY AND PHYSIOLOGY. 
Crust. 7 
The histological elements of the skin of the Oniscidce and Trichoniscus, 
with special regard to the cutaneous glands and ramified pigment cells, are 
described by M. Weber, Arch. mikr. Anat. xix. pp. 583-599, pi. xxviii. 
Unicellular glands in the skin of many Copepoda described by C. Claus, 
Arb. z. Inst. Wien, iii. pt. 3, pp. 6-9, pi. ii. figs. 1-9. 
6. Generation. 
M. Weber has examined the sexual organs of Trichoniscus and other 
Oniscidoi ; the appendages of the second segment of the pleon are really 
the intromittent organ, and their external shape is different in species of 
the same genus ; the large cells in the vesicula seminalis, which have the 
appearance of eggs, are probably rudimentary eggs, and it appears from 
them that the vesicula seminalis of the Oniscidce and other Isopods is a 
rudimentary ovary, the separation of the sexes in them being rather 
actual than strictly morphological. Arch. mikr. Anat. xix. pp. 623-648, 
pis. xxviii. & xxix. 
0. Nebeski states that in Orcliestia the hinder part of the testicle 
produces eggs, though in every other respect both sexes are quite distinct. 
Arb. z. Inst. Wien, iii. pt. 2, pp. 24-31, pi. iii. figs. 32 & 33, pi. iv. figs. 
34-38. 
7. Development. 
Imperfect metamorphosis in Alpheus (Say), the larva on 
hatching closely approximating to tlie form of the adult, observed by 
A. S. Packard, Am. Nat. xv. pp. 788 & 789, and Ann. N. H. (5) viii. 
pp. 447 & 448. 
B. Ulianin has examined the first stages of development in the eggs 
of several species of Orcliestia and Gammarus pcecilurus ; he describes 
the progress of cleavage, and dwells chiefly on the origin of the “ globi- 
form organ,” rejecting the opinions of previous authors concerning it, 
and suggesting that it may be an inherited part without physiological 
function, homologous to the shell-gland of the Mollusca^ and proving a 
nearer phylogenetic connection between the Arthropoda and Mollusca. 
Z. wiss. Zool. XXV. pp. 440-460, pi. xxiv. ; abstract in J. R. Micr. Soc. 
(2) i. pp. 599 & 600. 
The development of Cetochilus is the subject of a paper by C. Grobben. 
The cleavage is, according to him, bilaterally symmetrical ; after the 
32-cell stage there is a considerable pause, the blastomeres absorbing 
yelk-material. The endodermal invagination, the closing of the blasto- 
pore, and the moultings of the Nauplius are described. The genital 
organs make their first appearance very early, and are then paired and 
ventral in position, in the adult unpaired and dorsal. Arb. z. Inst. Wien, 
iii. 40 pp. with 4 pis. ; abstract in J. R. Micr. Soc. (2) i. pp. 734-736. 
8. Biology. 
M. Weber discusses the known instances of change of colour in liviug 
Crustacea : Gelasimus, Squilla, Mysis, Palo’mon, Nika, Idotea, and Pro- 
1881. [vOL. XVIII.] B IG 
