246 



BULLETIN 129^ UNITED STATES NATIONAL MUSEUM 



iC lO CO lO e^ O 



,-H ^ ^ ^ (y2oO 



CO CC CO CO i-H »o 



S S 





C3 S _^ S 



Ah b-3 a 



3S^§mag^l^ 



> 



St) 



a' m 



M-i 

 «-^ 



3^ 



'C _^H 



I>.C3 g 



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xa to 



3 .2 .5 



n 



a short branch runs up on the 

 branchial region. An irregular 

 row of small spines crosses the 

 gastric region. The orbits, outer 

 margin of the post-orbital teeth 

 and the infero-lateral and pos- 

 terior margins of the carapace 

 are armed with spinules. Ros- 

 tral horns more upturned than 

 in o'pilio and a little longer and 

 narrower, leaving a wider inter- 

 space. 



Posterior margin of epistome 

 strongly defiexed in the center 

 and arched at the sides. The 

 external maxillipeds when in 

 place do not fit closely into the 

 buccal cavity, as in opilio; 

 merus mth spinous margins. 

 Ambulatory legs armed with 

 longer and stouter spines than 

 in ojnlio. In adults more than 

 in young the legs are longer in 

 tanneri, especially the meropo- 

 dites, which are much narrower, 

 and in the male do not widen at 

 the proximal end as in opilio. 

 Legs of female shorter than of 

 male, as is the case in opilio. 



Second segment of male ab- 

 domen bent downward at lateral 

 extremities in almost a right 

 angle. On the sternum in front 

 of the abdomen there is a trans- 

 verse ridge of sharp tubercles. 



Men surem ents .^Male, holo- 

 type, length of carapace on me- 

 dian line 119, ■v\'idth exclusive of 

 spines 130, length of first ambu- 

 latory leg 316, length of its 

 merus 134, greatest width of 

 same merus '18.5 mm. 



Range. — From Washington 

 (lat. 47° 29' 30" N.) to the ex- 

 treme northern part of Lower 



