184 STALK-EYED CRUSTACEA. 
In full grown specimens of S. agassizii, which attain a length of 150 mm., 
the antennular flagella are only one half as long as the carapace, or even 
less. The flagella of the second pair of antennz are very slender and enor- 
mously long, — more than two and two thirds times the length of the whole 
body. The number of teeth on the rostrum and gastric region in full-grown 
individuals is nine. The sharply defined cervical groove does not quite reach 
the median dorsal line of the carapace, although the dorsal carina is inter- 
rupted at that point. The sides of the rostrum are tomentose, as appears to 
be the case in S. s¢phonocera and S. distincta (De H.). 
Measurements of a female (Station 3391): length of body, 149 mm. ; 
length of carapace, including rostrum, along median dorsal line, 54 mm. ; 
length of rostrum, 13.5 mm.; length of antennule, 46.5 mm.; length of 
antennular flagella, 28 mm.; length of antenna, 410 mm.; merus of third 
legs, 21 mm.; carpus of do., 36.5 mm. ; chela of do., 10 mm. ; antennal scale, 
22.5 mm.; telson, 22 mm. 
Station 3389. 210 fathoms. 2 males, 8 fem. 
Ce Niusliaer. tt 5 
The branchial formula of Solenocera agassizti is as follows: 
5 males, 6 fem. 
Somites VII. VIII. ie. Xie SLs SGky SOW BRIG 
Pleurobranchie 0 0 il 1 il af 1 ls © 
Arthrobranchie 0 2* 2 2 2 2 2 0 = 12 
Podobranchiz 0 1 0 0 0 0 0 = i 
Epipods i 1 1 1 1 1 i 0. = (7) 
CEG 
The pleurobranchia on the last thoracic segment is small but functional. 
The lateral branches of each gill are alternately arranged on each side of the 
main stem, and are curved so that their distal ends meet the ends of their 
fellows on the opposite side of the stem, and thus form a hollow tube which 
is open and obliquely truncated at the distal end. There are small exopods 
attached to all the legs. On the second maxillipeds the exopods reach to 
the end of the merus, but they gradually decrease in length through the 
series of following appendages. 
The geographical distribution of this interesting genus, as far as known, 
is as follows: S. siphonocera,+ the type of the genus, is found in the Mediter- 
* One of these is possibly a pleurobranchia rather than an arthrobranchia. 
+ Peneus membranaceus M. Bdw. (Hist. Nat. Crust., II. 417, 1837), nee Risso; Peneus siphonoceros 
Philippi (Arch. Naturgesch., VI. Jahrg., I. 190, Plate IV. Fig. 5, 1840) ; Solenocera philippit Lucas (Ann. 
Soe. Entomol. France, 2° Sér., VIII, 223, Plate VII. No. II. 1850); Solenocera siphonocera Miers (Proc. 
Zodlog. Soc. London, 1878, p. 301). 
