MORPHOLOGY. 
Crust. 21 
ing groups : — Ostracocla , p. 229; Branchiopoda , p. 236 ; Cladocera , p. 242; 
Argulidce , p. 244 ; Gopepoda , p. 245 ; Cirripedia, p. 252. 
Viallanes (C.R. cxii, p. 1017), after investigating the compound eyes 
of Macrura , comes to conclusions somewhat at variance with those of 
Patten. He believes the cone to be simply an organ of refraction. The 
segments of the cone are not continuous with the rhabdoms, but are 
connected by filaments with the basal membrane. 
Respiratory Organs and Appendages. 
Bouvier (Ann.Sci. Nat. (7) p. 402) discusses the gills of the Paguridce. 
Nusbaum deals with the locomotor appendages of Isopoda. 
Vascular System. 
Schneider (C.R. cxiii, p. 316) has investigated the arterial system of 
Isopoda. His researches go to snow that instead of having an anomalous 
and unique arrangement of vessels, as had been previously supposed, 
their arterial system strongly resembles that of the Ampliipoda. 
Bouvier (Ann. Sci. Nat. (7) xi, p. 197) has investigated the vascular 
system in Decapoda. The antenuary arteries always supply the eyes, and, 
in Brachyura , the rostrum, in conjunction with the ophthalmic artery. 
The liver derives its chief nourishment from the superior abdominal 
artery. The symmetry of the superior and inferior abdominal artery 
with their anastomoses is greatly destroyed in the Brachyura. The 
Decapoda resemble the Isopoda more than any other group in their arterial 
system. 
Nervous System. 
Richard (Bull. Soc. Z. Fr. xv, p. 212) gives a detailed account of the 
nervous system in Diaptojnus, as determined by the examination of 
several species of that genus. 
^Retzius deals with the nervous system of Crustacea. 
Samassa (Arch. mikr. Anat. xxxviii, p. 100) has investigated the 
nervous system of the Cladocera. The types studied were Sida crystallina, 
Daphnia sima , Bythotrephes longimanus , and Leptodora hyalina. A useful 
bibliography of the subject will be found on p. 129. 
Renal Organs. 
Weldon has discovered in several other forms the enormous bladder 
development which he first observed in Palcemon serratus ( J. Mar. Biol. 
Ass. (n.s.) i, p. 162). He arrives at the conclusion that “thenephro- 
peritoneal sacs of the Decapoda should be regarded rather as enlarged 
portions of a tubular system, such as that found in Mysis and in the 
Thalassinidee, than as persistent remnants of a ‘coelomm’ body-cavity, 
into which tubular nephridia open.” (Q. J. Micr. Soc. xxxii, p. 279.) 
