i^ 21 ! Schmitt: The Marine Decapod Crustacea of California- 73 



Characters. — Carapace carinated in its anterior half, posterior spine at the 

 anterior fifth; upper line of carapace and mid-rib of rostrum nearly horizontal; 

 rostrum about three-fourths or five-sixths as long as the carapace, upper and 

 lower limbs with convex margins and widest at about the middle of their length ; 

 armed above with ten to fourteen teeth, the last two or three of which are on the 

 carapace; armed below with one to three spines; tip acute. Eyes large, pyrif orm : 

 cornea extending on inner side almost to the base of the peduncle. Blade of 

 antennal scale exceeding the spine considerably, most advanced toward its inner 

 margin. 



Dimensions. — Type, female: length 62.6 mm.; length of carapace and rostrum 

 24 mm.; of rostrum 11 mm. 



Type Locality. — Off Tawhit Head, Washington, 178 fathoms ("Albatross" 

 station 3076). 



Distribution. — From the north coast of Unalaska eastward and southward 

 to Point Sur, California, 178 to 636 fathoms (Eathbun). 



Remarks. — The males exhibit the usual differences from the females (described 

 above) in being more slender, in the longer antennular flagella, and in the 

 abdominal appendages (Eathbun). 



Family Crangonidae (Alpheidae) 



Eostrum very small or wanting. Eyes covered by the carapace. Mandibles 

 with incisor process and palp of two segments. First pair legs chelate, with one 

 or both chelae powerfully developed. Second pair of legs minutely chelate, long, 

 slender, and equal, with segmented carpus. Telson broad and rounded. 



As the genera of Weber (Nomenclator entomologious, 1795) complying with 

 the International Code of Zoological Nomenclature are to be accepted as valid 

 (vide Smithsonian Publ. 1938, 1910) I have followed Miss Eathbun 'a findings 

 (Proe. Biol. Soc, Washington, 17, 170, 19046) and have given Crangon precedence 

 over Alpheus Fabricius. Hence the name of the family to which this genus belongs 

 becomes Crangonidae and the family formerly bearing that name must needs be 

 changed. For it Miss Eathbun (op. cit.) has supplied Cragonidae (p. 81), based 

 on the genus Crago, in place of the former genus Crangon. 



Key to the California Genera of the Crangonidae 



I. Eostrum present, short and pointed; hands normal, dactyl of larger hand 

 opening either vertically or horizontally; front either unispinose or tri- 

 spinose. 



A. No pterygostomian spine. Thoracic feet with epipods; dactyli sim- 



ple. (Not known north of the Farallon Islands.) 



Crangon, p. 74. 



B. Pterygostomian spine present. Thoracic feet without epipods; dac- 



tyli bifid. (Not known north of Santa Monica Bay and Santa 

 Catalina Island.) 



Synalpheus, p. 77. 



II. Eostrum wanting ; hands inverted so that dactyls are on lower side ; front not 

 spined, either emarginate between the eyes or evenly rounded. (Not known 

 north of Point Arena.) 



Betaeus, p. 79. 



