502 BULLETIN 129, UNITED STATES NATIONAL MUSEUM 



MICROPHRYS BRANCHIALIS Rathbun 



Plate 176, figs. 5 and 6; plate 270, fig. 1 



Microphrys, species, Rathbun, Proc. U. S. Nat. Mus., vol. 15, 1892, p. 254. 



Microphrijs branchialis Rathbun, Proc. U. S. Nat. Mus., vol. 21, 1898, p. 

 577, pi. 41, fig. 5 (type-locality, Magdalena Bay, Lower California, 12 

 fathoms; holotype. Cat. No, 21576, U.S.N. M.); Proc. Washington Acad. 

 Sci., vol. 4, 1902, p. 285. 



Diagnosis. — Postero-lateral angle armed with one spine. Antero- 

 lateral margin unarmed and without imbricated processes. Anterior 

 branchial region much swollen. Three marginal spines or teeth on 

 basal segment of antenna. 



Description. — -Anterior branchial region with an oblique oblong 

 protuberance, highest posteriorly, sloping gradually downward an- 

 teriorly and covered with tubercles. Gastric tubercles as follows: 

 Three median, a cluster of tliree on each side anteriorly, and a trans- 

 verse row at posterior end. One genital tuber- 

 cle; 10 cardiac, of which 2 are median. 

 Posterior branchial region with several tuber- 

 cles, arranged mostly in two longitudinal rows; 

 postero-lateral angle with a spine curving up- 

 ward. A row of blunt tubercles above poste- 

 rior margin. Margin of hepatic region with 

 a small tubercle; vertical side of branchial 

 region with scattered tubercles, and two lines 

 of tubercles continued to pterygostomian re- 

 FiG. 143.— MicEOPHEYs BEAN- glou. Ajitcrior and lateral regions hairy. 

 nTl AETicLE?x i3^r^ ^'^^^'^ Rostrimi deflexed; with two flattened, tri- 

 angular, acute horns, pointing forward and 

 separated by a V-shaped sinus reaching one-half length of rostrum. 

 Preorbital tooth subacute, denticulate; two superior orbital fissures 

 on either side of a rounded lobe; postorbital tooth blunt. 



Basal antennal article armed at antero-lateral angle with a long, 

 broad, blunt spine or tooth, curved inward and upward and with 

 crenulated outer margin; a short blunt tooth at base of second article; 

 a tooth on outer margin forming part of wall of orbit, and a laminate 

 tubercle near postero-lateral angle. 



Chelipeds of male one and a third times length of carapace; scat- 

 tered tubercles on upper surface of arm and wrist; a longitudinal row 

 on outer surface of arm, and two or three tubercles at proximal end 

 of outer lower margin. Palm long and narrow, margins parallel, 

 superior length over twice width and more than one and a half times 

 dactylus. Pollex not arched downward as in 21. platysoma. Cheli- 

 peds of female slenderer and about nine-tenths length of carapace. 



