1884] Zoölogy. 739 
___ Grustacea—H. W. Conn (Studies from the Biological Labora- 
_ tory, Johns Hopkins Univ.), contributes some thoughtful observa- 
_ tions and suggestions upon the signification of the larval skin 
_ with which the decapod zoea is covered on emerging from the egg. 
_ The apparent anomaly that certain low Macrura possess larve 
with a thorax, while the Schizopods havea zoea without a thorax, 
_ isexplained by the assumption that the zoea stage is an interca- 
lated adaptive form with the body shortened to enable the larva 
_ fo swim better, while the protozoea, represented by the zoea of 
_ Boas with that of Packard, and with the teachings of embryology. 
_ — Professor Greeff (Sitz. Ges. Natur. Marburg, 1882), gives an ac- 
_ Sount of the land and fresh-water crabs of St. Thomas and Rolas, 
_ in the Gulf of. Guinea. Gecareinus ruricola, known from the 
_ West Indies, occurs also in incredible numbers in the Guinea 
4 t is found even in the mountains, under stones, in holes 
_ inthe earth, and other damp places. Cardisoma guanhami, an- 
; other Antillean species, occurs with the former. Cwnobita ru- 
ga is common all over St. Thomas, and causes a great mixture 
s marine aud fresh-water shells. During their growth the crabs 
Wander inland, taking with them Murices, Bullidz and other ma- 
fine forms. Arrived at the mountains, 800 meters above the 
a ocean, met exchange these for Helixand Achatina in which they 
| Sard to the coast. The fresh-water species aré Pale mon olferst, 
3 Atya scabia and Thelphusa margaritaria. 
a s—On account of the possession of a drag-net adapted 
Sr the Purpose, the Za/isman was more fortunate than any pre- 
| ou exploring vessel in obtaining examples of deep-sea fishes. 
ice haul in 16° 52 N, lat., and.27° 50’ W. long.,and at a 
was Bythites crassus. Some of the species appear to in- 
very extensive zones of depth, thus Alepocephalus rostratus 
ra from 868 to 3650 meters, Scopelus maderensis from 1090 
re Meters, Lepioderma macrops from 1153 to 3655 meters, 
Wears to ; affinis from 590 to 2220 meters. This great range 
+e to Indicate a power of adaptation to the pressure of the 
ong the phosphorescent apparatuses found in these, 
of the €ep,/one of the strangest is that of Eustomias 
“a slender fish with a large mouth. From the under side 
t 
