242 STALK-EYED CRUSTACEA. 
An analysis of this list discloses the enormous — often cosmopolitan — 
distribution of deep-sea types and their lack of special affinity with the 
nearest littoral fauna. Only four new genera were found among the Stalk- 
eyed Crustacea taken at a greater depth than 500 fathoms, viz. Trachycar- 
cinus, Calastacus, Scolophthalmus, and Ceratonvysis. Of these, Zrachycarcinus 
(a Corystoid crab from 546-695 fathoms) is represented in deep water in the 
Caribbean Sea by an undescribed species which .is probably congeneric, and 
by Trichopeltarion (151 fathoms). Both of these genera are closely related 
to, and perhaps derived from, Hypopeltarium, a shallow water form found on 
the shore of South America from La Plata around Patagonia to Chile. Calas- 
tacus is allied to Calocaris of the North Atlantic, 150-400 fathoms. Scoloph- 
thalmus, a deep-sea Schizopod, is probably a near relative of Hansenomysis 
from off the west coast of Greenland, and it is worthy of note that both 
Scolophthalmus and Ceratomysis confess by their structure their kinship with 
Boreomysis, a genus which reaches its highest development near the arctic 
and antarctic regions. 
Tconavius has been previously known from remote parts of the Pacific, — 
near the Celebes and Kermadec Islands. The only other known species of 
Paracrangon inhabits Puget Sound and the seas near Japan. Sclerocrangon is 
without doubt a genus of boreal origin. It is represented in high northern 
latitudes by cireumpolar littoral species, and on both sides of the Atlantic by 
deep-water species that range as far south as 31° 57’ N. (S. agassizi). One 
of the “ Albatross” west coast species, S. procax, extends the range of this 
genus southward in deep water to within 4° 3’ of the equator (Station 3380, 
899 fathoms, bottom temperature 37° F.). The genus Pandalopsis is repre- 
sented in the “Albatross” collection by the same species that was discovered 
by the “Challenger” off Monte Video. Petalophthalmus was known, prior to 
the “ Albatross’ Expedition, only through the unique specimen obtained by 
the “Challenger” Expedition from a great depth in the tropical Atlantic. 
Like Scolophthalmus and Ceratomysis, it is related to Boreomysis. All the 
other genera included in the above list may be said to have a world-wide 
distribution. 
That the truly deep-sea Crustacean fauna of the Panama region has no 
special affinity with the littoral fauna of the same region may perhaps be 
more clearly shown by placing in two columns the distribution of the 
Panamian species found below 500 fathoms, or the habitat of representative 
species, when such are known. 
