DECAPODS 



119 



Rostrum long, narrow, grooved above, tapering to a narrow-acute tip 

 which is curved strongly downward and much compressed laterally. There 

 is no median gastric spine ; but with a lens one can discern a scabrous 

 granule in the spot where the spine usually occurs. The antennular pe- 

 duncle has shorter segments than in C. alba, to which 

 this species is nearly related ; outer branch of flagellum 

 as long as, or longer than, the blade of the antennal 

 scale. Antennae shorter than the body. Scale shaped fig. 59. Crangonsty. 

 as in C. alba, but much shorter, being only a little over cwrikoHsiand.^ "" ' 

 half as long as the carapace. Maxillipeds with the antepenult segment 

 outwardly dilated as in C. alba. The hands are slightly widened distally, 

 shorter and broader than in C. alba, the length being barely twice the 

 width ; the anterior margin is more transverse than longitudinal. Second 

 pair of feet more slender and a Httle longer than the third. 



Abdominal segments smoothly rounded above, not carinated ; sixth 

 segment not sulcated below ; seventh segment a very little longer than 

 the sixth. The luropods extend considerably beyond the telson. Each 

 segment in the male bears a median spine on the ventral side. 



Dimensions. — Length of female 54 mm., of carapace 15.1 mm., of 

 acicle 9.1 mm. 



Distributioti. — Santa Cruz, California, in seine, April 12, 1897 {^Alba- 

 tross) ; Trinidad, Humboldt Co., Cahfornia (Holmes) ; Chirikof Island, 

 Alaska, anchorage, 9-14 fathoms, sand (W. H. Dall). 



CRANGON DALLI Rathbun. 

 Crangon dalli Rathbun, Proc. U. S. Nat, Mus., xxiv, 889, 1902. 



Rostrum rather long and narrow, sides parallel for a portion of their 

 length, edges upturned. Second antennular segment about one and a 

 half times as long as the third ; inner flagellum exceed- 

 ing the acicle ; outer flagellum considerably shorter. 

 Acicle about seven tenths as long as the carapace ; blade 

 obliquely subtruncate, inner angle rounded, receding ; spine 

 extending beyond the blade to no greater extent than the 

 anterior width of the blade. The first pair of feet reach 

 only to the middle of the terminal joint of the maxillipeds ; 

 the hands widen considerably from the proximal to the 

 distal end ; the distal margin is transversely oblique ; the 

 '^ width of the palm is contained in its greatest length about 



Fig. 60. Crangon , . , . 



dalli. 8. Station two and two thirds tunes. 



3287. a. Dorsal view /• i i i i 



of rostral region (X The first to fifth Segments of the abdomen are smooth ; 



3). i5. Acicle (X 2)- 1.11 11 , • t • ^^• y ' 



c. Chela (X 4)- the sixth has two blunt but promment longitudmal carmae, 



