1909] McClt hiIoh: The Ophiurams of the Sam Diego Region. 39 



arm joint. Color of preserved specimen grey above, lighter 

 below. 



San Diego M. B. L. : 991, 1% miles N.W.N, of La Jolla, 80 fathoms. 



Genus Ophioplocus Ly. 1861. 



Disc closely and finely sealed above and below. Genital scales 

 hidden. Teeth. No tooth papillae. Numerous even, close set 

 mouth papillae. Side mouth shields wide and nearly or quite 

 meeting within. Three short arm spines. Upper arm plates, near 

 tip of arm. divided on midline into halves, which at base of arm 

 are removed to outer lower corner of joint on each side and sep- 

 arated by a number of supplementary pieces. Two short genital 

 openings in each interbrachial space, extending only half way to 

 the margin of the disc and beginning outside the side mouth 

 shields. 



Ophioplocus esmarki Ly. 



Figs. 6, 7. 

 Bull. Mus. Comp. Zool., Ill, pt. 1(1, p. 227, pi. V. 



Diameter of disc, 30 mm. Length of arm 2% times diameter 

 of disc. Disc and arms flattened. Radial shields nearly covered 

 by scales. Scales irregular and swollen, giving the disc a pebbled 

 appearance, the larger ones, above, being usually surrounded by 

 smaller ones. The scales on the ventral side smaller than those 

 on the dorsal and more uniform in size. Ten to twelve mouth 

 papillae. Mouth shields sub-triangular, aboral margin rounded. 

 Genital openings, two in each interbrachial space, beginning near 

 the mouth shields, the edges granulated, and the granulation 

 extending out to the margin of the disc. Tentacle scales usually 

 4-5 in number surrounding- each tentacle pore. Ventral arm 

 plates six-sided, narrowed behind, distal margin straight or 

 slightly incurved. Dorsal arm plates broken into a large number 

 of irregular pieces. Arm spines three in number, about two- 

 thirds the length of the arm joints. Color of preserved speci- 

 mens light or dark brown or bluish grey. 



San Diego to Pacific Grove. Shore to 40 fathoms. San Diego M. B. L. : 

 102.".. San Clemente, San Pedro, Sta. 5, 15 fathoms. Albatross: March 15, 

 1891, off Point Loma. TJ. S. N. M.: 12732 (a). Catalina Harbor, W. H. Dall 



