PART 1 GARTH : PACIFIC OXYRHYNCHA 465 



Genus MESORHOEA Stimpson 



Mesorhoea Stimpson, 1871b, p. 135. Rathbun, 1925, p. 546. 



Type: The Atlantic Mesorhoea sexspinosa Stimpson [by error, 

 sexpinosa], 1871, by monotypy. 



Description: This genus bearing an almost exact resemblance to 

 Solenolambrus in the form and armature of the carapace, the character 

 of the [legs], and that of the pterygostomian and hepatic channels, ex- 

 cept for the latter being deeper; differing, however, very importantly in 

 the afferent channels meeting at the middle of the endostome, and having 

 there a triangular projection and a deep notch in its vertical, laminiform 

 wall. Merus of the external maxillipeds acutely produced forward at its 

 internal angle, and behind it the palpus entirely concealed. Epistome 

 very short. Eyes small, and sometimes retracted into their deep sockets 

 so as to be almost entirely concealed. The basal [article] of the external 

 antenna somewhat shorter than the next [article]. (Stimpson, modified) 



Range: Eastern Pacific from San Juanico Bay, Lower California, 

 and Georges Island, Gulf of California, Mexico, to off Esmeraldas, 

 Ecuador; Galapagos Islands. Western Atlantic from off Pensacola, 

 Florida, to Flannegan Passage, West Indies; Puerto Rico. 4.5 to 90 

 fathoms. 



Mesorhoea belli (A. Milne Edwards) 

 Plate Za, Figs. 11, 11a; Plate 54, Fig. 1 



Solenolambrus bellii A. Milne Edwards, 1878, p. 163, pi. 29, figs. 6-6d. 

 Mesorhoea gilli Rathbun, 1893b, p. 235; type locality, Gulf of Cali- 

 fornia; type, U.S.N.M. No. 17370; 1898, p. 581. 

 Mesorhoea bellii, Rathbun, 1925, p. 548, pi. 201 ; pi. 280, figs. 1-4. 

 Crane, 1937, p. 65. Garth, 1946, p. 414, pi. 69, figs. 5, 6; 1948, 

 p. 32. 



Type: Female holotype, length 14 mm, width 18 mm, length of 

 manus 13 mm, of merus of cheliped 11 mm; in Paris Museum. 

 Type locality: Mexico. 



Localities subsequently reported, with collectors: Mexico: west coast 

 of Lower California: off Abreojos Point, 48 fathoms, and Magdalena 

 Bay, 12 fathoms, Albatross (Rathbun, 1898) ; Gulf of California: N of 

 Punta San Felipe, 33 fathoms (type locality of M. gilli Rathbun), S 

 of Tiburon Island, 29 fathoms, NW of San Pedro Nolasco Island, 71 

 fathoms, and S of Cabo Haro, outside Guaymas, 20 fathoms, Albatross 

 (Rathbun, 1893b) ; Santa Inez Bay, 18-40 fathoms, Zaca (Crane) ; 

 La Paz Bay, 21 and 26.5 fathoms, and off Ceralbo Island, 9.5-10 fath- 



