ART. -3 FRESH-WATER MUSSELS, ANODONTITES MARSHALL 7 



understanding of the true crispata will make the classification of 

 the species of the genus invalid. 



It will be well to direct attention here to a footnote b}'^ Ortmann 

 (1921, p. 589), as follows: " Bruguiere uses Anodontites as fcmi- 

 nini gerieins, and this should not be changed." Most authors have 

 used the name as masculine. 



Until recently the division of the edentulous naiades into genera 

 depended solely on conchological characters. Upon comparing the 

 various descriptions one finds that the description of one genus 

 would often fit one or more others. Casual mention was made in 

 some species of the ligamental scar, but it remained for von Martens 

 (1900, p. 523) to point out the real im.portance of the sinulus, and 

 his remarks are especially valuable in regard to South American 

 naiades. lieferring to Fischer and Crosse's classification of Ayio- 

 donta (1894), he says: "They do not mention the shape of the 

 sinulus, a notch in the hinge line, at the hinder end of the ligament. 

 This, I think, is an important character, the sinulus being deep, 

 triangular, with a sharp point, and vertically as deep as broad, in 

 the South American species, and, on the contrary, shallow and 

 rounded in the North American and European forms." 



Practically all the South American naiades with edentulous hinge, 

 such as ATiodontites and Leila., or wish a hinge bearing peculiar car- 

 dinal teeth and lacking lateral teeth, such as M onocondylaea^ Fossu^a^ 

 Dlplodontites^ have the sinulus large and nearly equilaierahy tri- 

 angular. In some of the elongate forms, such as Mycetopoda and 

 Mycetopodella^ the triangular form is not so distinct, probably being 

 modified by the great length in comparison to height found in thesQ 

 gene7-a. 



Turning now to the species crispata we find that neither Simpson 

 nor Ortmann understood it. Ortmann (1921) dealt with incorrectly 

 identified material from a locality far removed from the type local- 

 ity. Both Simpson and Ortmann seem to have been misled by 

 Bruguiere's specific name crispata. It evidently was used in the 

 sense of crimped, while Simpson, in dealing with A. reticxLla.ta 

 Sovrerby, and Ortmann with A. colomllensis Marshall, interpreted 

 it as meaning crinkled. " Crimped " and " crinkled," although 

 both translate crispata, are very different, the former conveying the 

 idea of regularity in the wrinkling, and the latter the idea of being 

 wrinkled or rumpled with little regard to uniformity. " Crimped " 

 nicely describes the sculpture of A. crispata, while " crinkled " 

 describes that of the other two species. 



The Carnegie Museum kindly sent me for examination the speci- 

 men identified as A. crispata Bniguicre by Ortmann and figured by 

 him (1921) on Plate 41, Figures 2a, 2b, and generously donated two 

 specimens from the same lot as the figured specimen. The locality 



