458 FRESH-WATER BIOLOGY 



But whether the nemerteans from these widely separated local- 

 ities represent a single or several distinct species is not yet defi- 

 nitely known. Since fresh-water nemerteans similar to ours are 

 found in England, Germany, and other parts of Europe, and in 

 Asia and Africa, a careful study of specimens from many Ameri- 

 can localities is necessary to settle the question of nomenclature. 

 For it is not improbable that some of the localities mentioned 

 have been stocked with forms -transported from other parts of the 

 country, or from other quarters of the world. The importation 

 of cultivated water plants furnishes ideal conditions for the intro- 

 duction of the nemerteans associated with them. 



A recent study indicates that the species found in Connecticut 

 is identical with that recorded by Montgomery from Pennsylvania. 

 This species differs in certain anatomical details from any of the 

 described exotic forms, but is evidently synonymous with Leidy's 

 Emea rubra. Since there is nothing in the published descriptions of 

 specimens from other North American localities to indicate a spe- 

 cific distinction it is at present possible to recognize but a single 

 species, to which the name Stichostemma rubrum (Leidy) should be 

 applied. 



IMPORTANT REFERENCES ON FRESH-WATER NEMERTEANS. 



BOHMIG, L. 1898. Beitrage zur Anatomic und Histologie der Nemertinen. 

 [Stichostemma graecense (Bohmig), Geonemertes chalicophora (Graff).] Zeit. 

 f. wiss. Zool., 64: 479-564. 



Detailed account of the structure of a fresh-water form. 



BURGER, O. 1895. Die Nemertinen des Golfes von Neapel und der an- 

 grenzenden Meeres-abschnitte. Fauna u. Flora v. Neapel, Monogr. 22. 



Important monograph on the European nemerteans. 

 CHILD, C. M. 1001. The Habits and Natural History of Stichostemma. 



Am. Nat., 35: 975-1006. 

 HARTMEYER, R. 1909. Nemertini. Die Susswasserfauna Deutschlands, Heft. 



19: 47-48. 



MONTGOMERY, T. H., JR. 1895. Stichostemma eilhardi nov. gen. nov. spec. 

 Ein Beitrag zur Kenntnis der Nemertinen. Zeit. f. wiss. Zool., 59: 83-146. 



Anatomical study of a fresh- water nemertean. 



1896. Stichostemma asensoriatum n. sp., a Fresh -water Nemertean from 

 Pennsylvania. Zool. Anz., 19:436-438. 



Description of a fresh-water nemertean from Pennsylvania. 



