NEW makinp: worms of the oenus myzostoma. 



By J. F. McClexdox, 



Of liiiiidolpli-Mdcoii College, A.^JiIuihI, Virg'mia. 



At the request of Dr. Richard Rathbun, Acting' Secretary of the 

 Smithsonian Institution, last Ma}', 1 examined for niyzostomes the 

 crinoids and ophiurans in the Smithsonian Institution, other than 

 those examined previously/' and found three new species and one new 

 subspecies, besides one species previously described. To this list I have 

 added two specimens of J/, chirlxi sent to me by Doctor Rathbun too 

 late to be considered in my former paper. 



Yellowish brown, circular 



MYZOSTOMA CUBANUM, new species. 



One specimen from Crinoid Cat. No. 1H898, U.S.N.M., dredged 

 by the U. S. Bureau of Fisheries' steamer Alhafross at Station 2156, 

 oil' Habana, 289 fathoms, April 3o, 1884. 



Diameter, 1,7 mm. Thickness, 0.8 mm. 

 in outline, very flat on the 

 dorsal surface, v/ith lo pairs 

 of short conical cirri around 

 the edo-e. Ver}- convex (ap- 

 proximately hemispherical) 

 on the ventral surface. The 

 parapodia are prominent and 

 decrease slightly ui size 

 toward the posterior end. 

 The mouth and arms are 

 very minute and are terminal in position. On the dorsal surface are 

 peculiarly elevated areas with very much contorted outlines. The 

 median one of these extends from the anterior to the posterior end. 

 On each side of the median a primary, secondary, and tertiary set of 



<'The Myzostomes of the Albatross expedition to Japan, by. I. F. McCIendon, Bull. Am. Mus. Nat. 

 Hist., XXni, 1906, pp. 119-130, pi. xv-xvil. 



1.— Myzo.sto3i.\ ci banu.m. 



VENTKAI, VIEW. 



Proceedings U. S. National Museum, Vol. XXXII— No. 1509. 



63 



