PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 5 
The number and arrangement of the dorsal spines of the carapax 
appear to be nearly as in A. hystrix Stimpson, as figured by A. Milne- 
Edwards (Crust. Région Mexicaine, p. 134, pl. 28, fig. 1, 1878), except 
that the lateral spines of the gastric region are obsolete in A. Tanneri ; 
but all the spines are very greatly longer in hystrix, which appeats to be 
a very distinct species. 
Measurements in millimeters. 
Station— 
1038. 1043. 
ee ee tees oo tao cca civ aanwe cade We maldimsente nesses ccegvecos aelpaceamants oats fol fof 
Length of carapax, including rostral and posterior spines.......-.------------++----- 15+ 28.0 
Length of carapax from base of rostral to tip of posterior spines ------..-.-----.----- 11.0 18.0 
Length of carapax, excluding rostral and posterior spines.......-----.....----------- 10. 2 16. 2 
DOmeiMeLOst MOLI S' OT SPOS) 4-2 i) oe Saco ch s dca c'ss yoesis gic tbaice oces sac uecice caps 44 11.0 
Breadth of carapax, including lateral spines 10. 0 18.0 
Breadth of carapax, excluding lateral spines 6.7 11.2 
Length of branchialspine ......-..-.-.----- 1.9 4.0 
Length of cheliped ..........-- 12.0 20. 0 
Length of chela.......-.....-- Bae 9.0 
Breadth of chela............-- 1.1 1.8 
Length of dactylus........--. 2.0 3.5 
Length of first ambulatory leg.. 21.0 35. 0 
Length of dactylus ................. 3.7 6.2 
Length of second ambulatory leg .- 222. 2.22. 22s 20 enone cone wn en ensececncn-eeeenn oes: 16. 0 27.0 
PPM PMsCIC UV LUN Sec mec cass haat f oe teee tocadep van aeeescecenteucdcuenecetadeteeacee 3.0 5.0 
Specimens examined. 
Z : 
g = No. of speci- 
° Locality. 2 = Se 
vA = | Nature of bottom. ia 
— =) 
=| 
£ | Nilat. W. long. | = 8 
E a e (4 g 
a = e 
OFF MARTHA’S VINEYARD. H 
Cre Sie 1881. 
1038 | 39 58 70 06 146 S. Sh. Sept. 21 | ly. 
OFF DELAWARE BAY. 
OTe” om 1881. 
1043 38 39 73 11 130 S. Oct. 10 | 1 
Hyas coarctatus Leach. 
Taken at a number of stations off Martha’s Vineyard, in 86 to 158 
fathoms, and also in much shallower water near Block Island and off 
No Man’s Land. Four male specimens were taken off Chesapeake Bay 
in 1880, station 900, N. lat. 37° 19’, W. long. 74° 41’, 31 fath., sand— 
the farthest south the species has been noticed. 
Collodes robustus, sp. nov. 
Collodes depressus Smith, Proc, National Mus., iii, p. 414, 1881 (mon A. M.- 
Edwards. ) 
A careful examination of one of the type specimens of C. depressus 
convinces me that the specimens which I have referred to that species 
