1901.] NATURAL SCIENCES OF PHILADELPHIA. 289 



THE IDENTITY OF THE GORDIACEAN SPECIES, CHORDODES MORGANI 

 AND C. PUERILIS. 



BY THOMAS H. MONTGOMERY, JR. , PH. D. 



In a preceding contribution^ I described as new and distinct 

 species Chordodes morgani and C. puerilis, the former based on 

 two females, the latter on two males. The differences in the sculp- 

 turation of the surface of the cuticle seemed then to justify the 

 separation of these two species. In a later paper^ 1 stated that 

 " Chordodes pxierilis and 0. morgani may eventually be found to 

 be the two sexes of the same species;" and the truth of this sup- 

 position is now confirmed. C. puerilis thus becomes a synonym of 

 C. morgani, since the latter was first described in the original paper. 



Matei'ial consisting of seven females and five males, all collected 

 together at the same time (July 27, 1899), on the shore of South 

 Bass Island, in the western end of Lake Erie, in the explorations 

 of the Great Lakes conducted by the U. S. Fish Commission, were 

 very kindly sent to me for identification by Prof. Jacob E. Reig- 

 hard; and I am indebted to him and to Mr. George M. Bowers, 

 Fish Commissioner, for permission to publish my conclusions. An 

 examination on cross sections of the cuticle of a number of these 

 specimens shows very considerable variation, but variation with 

 intergradation; and shows also that there is more or less of a sex- 

 ual difference in the form of the papillse of the cuticle. In each 

 individual the cuticle of the middle region of the body was ex- 

 amined. 



In the following description the original specimens, as well as 

 the new material, shall be described together. In my first paper 

 the form of the body was described, and there is nothing new to 

 be added to that account. 



' " The Gordiacea of Certain American Collections, -with Particular Eefer- 

 ence to the North American Fauna," Bull. Mus. Comp. Zool., Harvard 

 College, Vol. 32, Xo. 3, 1898. 



■'"Synopses of North American Invertebrates. II, Gordiacea (Hair 

 Worms)," American Naturalist, Vol. 33, No. 392, 1899. 



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