1909] McClendon: TJie Ophiurans of tfa San Diego Region. 3.3 



disc over base of arm. Four genital openings in eaeli inter- 

 brachial space; the first pair begins at the outside of the mouth 

 shield. 



Ophioderma panamensis Ltk. 



Fig. 1. 

 Additamenta ad Hist. Oph., II, p. 193. 



Diameter of disc L'o mm. Length of arm about 3%-4 times 

 diameter of disc. Disc granulated above and below so that only 

 a minute portion of each radial shield is uncovered. Mouth 

 papillae and teeth small. Mouth shields sub-triangular with the 

 corners much rounded. Side mouth shields hidden by granules. 

 Pour genital openings in each interbrachial space. Tentacle 

 scales flat and continuous with arm spines. Ventral arm plates 

 about as broad as long, with corners rounded. Dorsal arm plates 

 two to three times as broad as Ions with distal margin concave 

 and corners rounded. Arm spines numerous, flattened, lying 

 close to arm and shorter than arm joints. Color dark brown 

 above, lighter below, the arms encircled by pale bands. 



A common littoral species of the region. Panama to San Pedro and 

 < latalina. San Diego M. B. L., La Jolla. Albatross stations 3588, 3589 and 

 3590, San Diego Bay. Smithsonian 521:'., Catalina Id.; No. 1 San Diego (H. 

 Hemphill). U. S. Nat. Mus. 12732 (ft) Catalina Harbor 30-40 fathoms I W. 

 H. Dall c 6 1874). 



Family 2. ( Iphiolepididae Ljg. 1867. 



Three to four mouth papillae, of which the innermost is sel- 

 dom below the teeth. No tooth papillae. Notch in disc above 

 base of arm. Two genital openings in each interbrachial space. 



Genus Ophiomusium Ly. 1869. 



Teeth. No tooth papillae. Mouth papillae fused in a con- 

 tinuous row so that their former outlines are indistinct. Disc 

 covered by plates and radial shields, all of which are fused. Up- 

 per and under arm plates minute, side arm plates meeting above 

 and below, swollen and fused with neighboring plates. No ten- 

 tacle pores beyond the basal arm joints. Small arm spines on 

 outer edge of arm plates. Two genital opening's in each inter- 

 brachial space. 



