1909] McClendon: Tlu Ophiurans of tht San Diego Region. 45 



Sub-genus Amphiodia Yen-ill 1809. 

 Three (rarely 4) small, subequal mouth papillae, none of 



the perculiform. They form a regular series attached mostly 



to the side jaw plate. No distinct oral tentacle scales. Three 

 (rarely 4) arm spines. Radial shields often more or less joined. 



Amphiodia barbarae Ly. 



Figs. 22, 23. 

 111. Cat. Mus. Comp. Zoo. Harvard, VI U, pt. 2, p. 17, pi. III. 



Diameter of disc 4 mm. Length of arm ahont 12 times diam- 

 eter of disc. Disc covered with small imbricated scales. Radial 

 shields naked, meeting along outer two-thirds of length, twice 

 as long as broad. Three pairs of thick mouth papillae. Teeth. 

 No tooth papillae. Mouth shield quadrangular, outer angle more 

 obtuse, corners rounded. Side mouth shields very slender, meet- 

 ing within, outer ends knobbed. Genital pores beginning at 

 mouth shield. Two very short, flat tentacle scales. Ventral arm 

 plates heart-shaped, with apex proximally. Side arm plates 

 meeting below. Dorsal arm plates elliptical, about twice as broad 

 as long. Three tapering arm spines, subequal, a little shorter 

 than an arm joint. Color of dried specimen yellowish, disc some- 

 times greenish. 



San Diego to Santa Barbara. San Diego M. B. L. : San Pedro, Station 

 1-1, May 22, 1901. San Pedro, Station (8), June 25, 1895. XXXI -a, 

 June, 1901. XXXIV-a, up Little Harbor Valley, June 28, 1901. XXXVI-c, 

 June, 1901. LXXIII-1, off Pt. Lonia, July 25, 1901, 120 fathoms. 974, 

 1% miles N.W. by N. of La Jolla, 85-100 fathoms. 1112. 



Specimens from San Pedro (8) and XXXVI have more rect- 

 angular dorsal arm plates and some have more pointed mouth 

 papillae. In young specimens from XXXIV-a the scales on edge 

 of disc project as trificl spines. 



Genus Ophiocnida Ly. 1865. 

 Disc small and delicate, furnished with naked radial shields 

 and naked overlapping scales, the latter beset with small thorns 

 or grains. Teeth. No tooth papillae. Mouth angles short and 

 small, bearing a few (4-6) little mouth papillae. Arms long, 

 slender, even, more or less flattened. Arm spines short and reg- 

 ular. Two genital openings in each interbrachial space. 



