14 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 24 



Orthochela pumila Glassell 

 Plate 18, fig. 1 ; text-fig. 1 



Orthochela pumila Glassell, 1936, p. 296, pi. 21, fig. 1 (type locality, Isla 

 Santa Margarita, Bahia de la Magdalena, Baja California, Mex- 

 ico). 



Previous records: Baja California. Isla Santa Margarita, Bahia de 

 la Magdalena: S. A. Glassell (Glassell). 



Diagnosis: Carapace a little less than one and a half times as long 

 as broad; front nearly as broad as carapace, truncate, with strongly 

 projecting median lobe; lateral margins subparallel, with about twelve 

 to fifteen close-set spinules posterior to epibranchial angle; chelipeds 

 subcylindrical, held straight out in front of carapace. 



Description: Carapace a little less than one and a half times as long 

 as broad, transversely convex, lightly granulate or punctate, regions not 

 distinct; devoid of pubescence. Front very broad, flat, not deflexed; 

 median lobe triangular, truncate and with several minute spinules at tip ; 

 lateral lobes a little broader than median lobe, minutely spinulate along 

 their inner (anterior) margins. Orbits broad, deeply concave; outer 

 orbital angle produced into a broad tooth. No epibranchial spine, but 

 epibranchial angle marked by a distinct notch; lateral margin posterior 

 to this notch and cervical groove with about twelve to fifteen close-set 

 spinules, the posterior ones slightly the largest. 



Text-fig. 1. Basal segment of right antennule of Orthochela pumila, x 56. 



Movable segments of antenna more or less smooth ; flagellum naked. 

 Outer maxillipeds lightly rugose. 



Chelipeds similar in form but one distinctly larger than the other; 

 larger cheliped about two and a half times length of carapace in largest 

 specimens; smooth to lightly granular, devoid of hairs. Merus extend- 

 ing to or beyond tip of median frontal lobe, with a low lobe on its an- 



