l8 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 73 



OPINION 117 



Type of Lithostrotion 



SUMMARY. — Under Suspension of the Rules Lithostrotion is hereby stand- 

 ardized, with Lithostrotion striatum as type species, and is placed in the 

 Official List of Generic Names. 



Presentation of case. — By Dr. W. D. Lang and Dr. S. Smith: 



We wish the species Lithostrotion striatum to be standardized as the genolec- 

 totype of Lithostrotion. The history is as follows : 



Lithostrotion Fleming, 1828, History of British Animals, p. 508. 



Genosyntypes : 



L. striatum, 1828, p. 508. 



Erasmolithus Madreporites floriformis; Martin, 1809, Petreficata Der- 



biensia, pi. 43, figs. 3 and 4; pi. 44, fig. 5. 

 L. obliquum; Fleming, 1828, p. 508. 

 L. marginatwn; Fleming, 1828, p. 508. 



In 1845, Lonsdale (in Murchison, Geology of Russia, vol. i, p. 602) mentions 

 four species of Lithostrotion, namely L. cmarciatum, L. mammillare, L. astroides, 

 and L. florijorme. Without definitely designating L. floriforme (the only geno- 

 syntype involved) as lectotype, he yet discusses and determines the characters 

 of Lithostrotion upon L. floriforme, clearly implying that he considered L. 

 floriforme as lectotype. But if the author's intention is considered, it might be 

 argued that Fleming intended L. striatum as genotype of Lithostrotion, since 

 he placed it first, and gave it the trivial name striatum which, with the name 

 Litliostrotion, is an echo of Lhv^ryd's description " Lithostrotion sive Basaltes 

 minus striatum et stellatum," to which Fleming refers in his description of 

 L. striatum. 



Since, however, a genolectotype must be deliberately designated ("the mean- 

 ing of the expression 'select the type' must be rigidly construed"), we are 

 bound to leave both Fleming and Lonsdale with their implied intentions, and 

 pass on to Edwards and Haime, who, in 1851 (Mon. British Fossil Corals, 

 p. 72) deliberately designated L. floriforme Fleming, as genotype of Lithostro- 

 tion; and the fact that thereafter both they, and nearly all other authors, aban- 

 doned this ruling, interpreting Lithostrotion as if the genolectotype were L. 

 striatum, and including L. floriforme in McCoy's genus Lonsdaleia, does not 

 invalidate Edwards and Haime's prior pronouncement. L. floriforme, then, still 

 stands as the genolectotype of Lithostrotion. 



Now the generic type of the coral which, since 185 1, has been almost univer- 

 sally, though wrongly, ascribed to Lithostrotion, is very abundant in the Car- 

 boniferous Limestone and includes several separable forms. The same is true 

 of the genus Lonsdaleia of which the genolectotype is L. dupticata (Martin) 

 and which includes the species of L. floriformis (Afartin), i.,e., the Lithostrotion 

 floriforme of Fleming and the true genolectotype of Lithostrotion. It is easily 

 seen, therefore, that much of Carboniferous Coral nomenclature is thrown into 

 confusion by giving the correct interpretation to Lithostrotion; and that time, 

 labor, and misunderstanding would be saved, if the species L. striatum, which 

 the author of Lithostrotion clearly intended as genotype, should be standardized 

 as genolectotype of Lithostrotion. 



