12 PROCEEDINGS OF THE NATIONAL MUSEUM vol.79 



while it is a true Anodontites and groups with A. tortoJa Lea, A. 

 pittieri Marshall, and some others that show a rather distant rela- 

 tionship to cris'pata^ it is distinctly different from it, as might have 

 been expected from the fact that it comes from Peru, while crispata 

 comes from French Guiana. 



Anodon reticulatus Sowerby, as shown by its description and by 

 specimens in the United States National Museum, does not even 

 belong in the section Anodontites s.s. with A. crispata^ but probably 

 in the section Sty g anodon with A. tenehricosa and others. 



With the above explanations the synonymy of Anodontites crispata 

 Bruguiere will be as follows : 



1792. Anodontites crispata Bruguieke, Journ. d'Hist Nat., vol. 1, p. 131, pi. 8, 



figs 6, 7. 

 179S. Anodontites crispata IJkuuuieeb. Ency. Metli., vol. 1, pi. 203, figs. 3a. 3h. 

 1S19. Anodonta crispata Lamarck, Hist. Nat. Animaux sans "Vert., vol. G, p. 86 



(with a reference to Eucy. Metli., pi. 203, figs. 3a, 3b). 

 1870. Anodon schomhurgianus Sowerby, Coiicli. Icon., vol. 17, pi. 34, fig. 137. 



(British Guiann.) 



Haas (1931, p. 95), in his treatment of A. crispata Brug., adds 

 the mistakes of Simpson to most of those of Ortmann and hence 

 this portion of his work is to be rejected, except, perhaps, his cita- 

 tion of Cayenne, French Guiana, as the source of one of his speci- 

 mens. This may be the true A. crispata. His citations of locali- 

 ties in Colombia and Ecuador are erroneous. They probably refer 

 to specimens of A. colomhiensis Marshall (Colombia) and A. 

 napoensis Lea (Ecuador). Haas has made matters worse by plac- 

 ing A. napoensis Lea in the synonymy of A. crispata Brug., while 

 he places the very closely related A. colomhiensis Marshall in the 

 synonymy of A. soleniformis Orbigny. 



Marshall (19ol, p. 16) describes the new subgenus Rug anodontites 

 to include the two species A. colomhiensis Marshall (type) and A. 

 napoensis Lea. 



NOTE ON THE LASIDIUM 



Ihering (1891, p. 480; 1893, p. 48) described and figured the em- 

 bryo of Anodontites wymanni Lea, and stated that the embryos occur 

 in the inner gills. He called the embryo a lasldium. Having three 

 pieces it is entirely different from the glochidiwn, which has two 

 pieces, commonly found in naiades. Since that time '" lasidiiim " 

 has had frequent and important mention in classiiication. Because 

 of Ihering's eminent standing as a naturalist we are compelled to 

 accept his findings until they are proved to be incorrect, but in 

 biology we give great respect to analogy, and his discoveries are so 

 different from what we should expect from the analogy between 

 Anodontites^ Diplodon, Anodonta., Unio., and other naiades that we 



