PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 7 
shorter, and the last considerably less than twice as long as the cara- 
pax; the dactyli are considerably curved, slender, and tapered near 
the acute chitinous tips. 
The sternum is tuberculose, like the dorsal surface of the carapax, 
except upon the concave portion between the bases of the chelipeds, 
where it is smooth. 
The first somite of the abdomen is tuberculose, like the carapax, and 
armed with a low tuberculiform prominence, in place of the spine in the 
young. The second somite is very short and scarcely wider than the 
first. The third is widest of all, and from it the abdomen is regularly 
narrowed to the seventh somite, which is anchylosed with the sixth, as 
in Euprognatha rastellifera, triangular, with the tip obtuse, and nearly 
as broad as long. 
Female.—The females appear not to attain the adult sexual char- 
acters until the carapax is about 12™™ in length, apparently never 
attain as great size as the males, and as usual aeons the young, 
although they lose the gastric, cardiac, and abdominal spines fully as 
early as the males. The carapax is slightly more convex and the bran- 
chial regions somewhat less swollen than in the male. The chelipeds 
remain small and weak, the chelw slender as in the young, and the am- 
bulatory legs proportionally shorter than in the male. 
The proportions of the carapax, chelipeds, and ambulatory legs in the 
young and adults of both sexes are well shown by the accompanying 
table of measurements. : 
Measurements in millimeters and hundredths of length of carapax. 
Station— 
™ 
874 | 949 | 940 | 940] 940| 940] 873 | 10386 | 950 940 
Sex -..-.-.0020- 222-00. o-vere oneness fae od |) et lett al] yas | oP} con Fig 
Length of carapax, including frontal 
EGIL | g 3S26 eRe Peo eeee | 9.7 | 12.5 | 14.8 | 23.3 | 25.7] 27.0] 8.2 | 10.7'| 13.3 | 18.3 
Greatest breadth of carapax.....-..-.. C16) SOY PLOKB  LT9) | 2057 1 212 ons PO BOo8)|" 14.1 
gs in hundredths of length of cara- | 
ee eeeeen men: Heh aos \owaeate car miae 68 73 73 77 77 78 71 68 | 70 77 
Segre GiNPMNEd 5-2-2. os cen cee ne | 11.0 | 16.0 | 18.0 | 34.0 | 38.0 | 40.0] 9.5] 11.0] 14.0] 19.0 
Length IMOHOLaA es © Sess ose ee Se | 4.8] 62] 7.8] 14.8/17.6/185] 3.5) 4.5] 5.5 7.9 
aoe in hundredths of length of cara- 
= a ARES ek? a 149 |50 |53 |64 |66 |68 | 41 | 42 | 42 43 
Heicht Tg id ChE MR SU eee oe eee M250 |. 20] 66h 75) 8.0)" 09,1". T 4 2.1 
Sees in hundredths of length of cara- 
BEER a ta oeies Sera s Sekt sb sleeeeejeeniss'e 12 17 18 28 29 30 il 10 11 12 
Earth UPA EVO ny OT ee 2d Hid.) | Ae 4 16. ONH 9) Pel OS Sy SOs) Oi 68.8 4.7 
Length of first ambulatory leg......-. 20.0 | 28.0 | 34.0 | 58.0 | 65.0 | 68 0 | 15.0 | 19.0} 24.0] 32.0 
Length of propodus ..-..........--.-- 5.0] 65] 85) 14.5 | 15.5) 17.0] 3.1] 41] 60 TAS 
Lensth Oh GaCtylUse 25st. ca 3.9] 5.4) 7.0] 12.0) 134/145) 2.7) 3.9] 5.2 7.0 
Length of fourth ambulatory leg..... 17.0 | 22.0 | 27.0 | 42.0 | 46.0 | 47.0 }.....- 15,5 | 20.0) 25.0 
Length of propodus .......-----.--..- 3.8| 5.0| 69] 10.1 | 12.0 | 12.6 ]...... 2.91 4.8| 6.7 
Length of dactylus.-....-.-..-.--....- 38; 5.0) 6&3) 9.2) 100 | 10.2 )...... 2.8 | 4.7 6.2 
* Immature individuals. 
The number and arrangement of the branchize are the same as in 
Euprognatha rastellifera, but there are well-developed epipods on all 
