Boone, Crustacea, Cruise of "Alva," 1931 



129 



finger ; the lower finger is thicker proximally than the upper with 

 decidedly upcurved acuminate tip overlapping on the outer side 

 of the tip of the upper finger. The cutting edge of the lower 

 finger is channelled, beset with tufts of bristles; the outer distal 

 surface also bears bristles. The upper finger is slender, similarly 

 tipped, the apex overlapping on the inner side of that of the lower 

 finger, the cutting edge channelled. A slight oblique gape is pres- 

 ent between the two fingers. Both fingers are beset with bristles 

 in the channelled cutting edge ; the upper finger is also abundantly 

 beset with bristles on the distal half of the outer and lateral sur- 

 faces and somewhat less so proximally. 



// . y? Y'T'^i 



Text figure 9 — Alphens ventrosus (H. M. Edwards), sketch of open cheliped, 

 showing tooth ; from a different specimen than that shown in plate 33. 



The larger great cheliped is approximate-y five-sixths as long 

 as its companion, with the meral and carpal margins similar, ex- 

 cept that the merus is more deeply excavate on the ventral surface 

 for reception of the reflected propodus ; the propodus is swung 

 more obliquely and the related fingers have a distinct curvature, 

 or bowed aspect when viewed from the outer lateral side, the distal 

 portion of the fingers is bent outward. The upper and outer proxi- 

 mal portion of the palm has the same circumscribed area defined 

 by a linear sulcus as does the opposite cheliped. The proximal 

 portion of the palm above the finger is strongly and a little oblique- 

 ly truncated for the support of the opened finger ; there is a cir- 

 cular spot defined on this distal area. The lower finger is short, 

 thick, the cutting edge curved externally, is sinuate with a strong 

 rounded molar and beyond this obscurely a second less pronounced 

 tooth, the tip of the finger is very acuminate, overlapping on the 

 outer side the similar acute apex of the upper finger. The upper 

 finger has a sinuate cutting edge interfitting with that of the lower 



