512 



CRUSTACEA. 



Family II. CALLIANASSID^. 



Callianassa gigas. 



Frons paulo triangulatus. Manus major valde compressa, Icevis, carpo 

 non duplo longior, digitis brevibus, dimidio manus brevioribus, sparsim 

 hirsutis, consimilibus, non hiantibus, superiore arcuato, acuto, brachio 

 angusto, ad basin infra dentigero sed vix latiore, paululo longiore 

 quam carpus, intus vix dentato. Segmentum caudate appendicibus 

 caudalibus vix brevius. 



Front low triangular. Hand very much compressed, thin, smooth, 

 not twice as long as carpus, fingers short, not half as long as hand, 

 nearly similar in form, sparsely hirsute, not gaping, the upper 

 arcuate and acute, not dentate within ; arm narrow, below at base 

 having a tooth, but not much broader there on this account, little 

 longer than carpus. Caudal segment scarcely shorter than the 

 appendages. 



Plate 32, fig. 3 a, animal, natural size; b, eye, enlarged; c, arm; d, 

 inner antennas. 



Puget's Sound. — Lieut. Case. 



Length, four and a half inches. The outer antennas are often 

 thrown directly back along the carapax, by a flexure at the second 

 and third articulations of the base. The longitudinal sutures of the 

 carapax are very nearly straight. The posterior portion of the cara- 

 pax is but little more than one-third the length of the anterior. The 

 eye-peduncles are flat, and the eye is near the middle of the upper 

 surface. The right of the anterior feet is the larger in our two speci- 

 mens. The carpus is as broad as the hand ; its length equals the 

 length of the hand, exclusive of the fingers, and its breadth is about 

 three-fourths the length of the arm. 



