On the Genus Lasiodora, C. Koch. 337 



much used by Dr. A. S. Woodward, that in evolution the 

 dermal fin-rays become correlated with the endoskeletal tin- 

 supports. 



Finally, as all Osteolepids have an archipterygial fin, with 

 only a single element articulating with the pectoral girdle, we 

 have to take into consideration tlie somewhat Teleost-like 

 skeleton of the pectoral fin found in Ccelacanthus according 

 to Well burn and in an undetermined Ccelacanth described by 

 Smith Woodward. 



The whole literature is listed and discussed in E. A. Stenslo, 

 'Triassic Fishes from Spitzbergen ' (Adolf. Holzhauseii, 

 Vienna, 1921). 



1 have to acknowledge my indebtedness to Mr. Gr. E. 

 Dibley for the loan of specimens, two of which proved 

 invaluable in my studies. 



XXX. — On the Germs Lasiodora, C. Koch. By MellO- 

 LeitaO, M.D., Fellow of the Brazilian Society of Sciences. 



The genus Lasiodora, C. Koch, is essentially neotropical, and 

 all its species but one {L. iceijenherghi^ Thorell, from Argen- 

 tiini) are found in the Brazilij.n fauna. I have seen in the 

 collection of the Natural History Museums of S. Paulo and 

 Kio de Janeiro specimens of all the Brazilian species. 



Lasiodora differs from all the other Lasiodoreae, Simon, in 

 having a stridulating-organ similar to that of Grummostola ; 

 but in Lasiodora the stridulating bristles are much less 

 numerous, and those on coxa i. are situated only upon the 

 suture. The characters of this stridulating-organ distinguish 

 the species, the number and disposition of the striduhiting 

 bristles being variable. I give the following tabic of Bra- 

 zilian species : — 



A. Falces.with a rose-thorn-like spur in the 



external surface acanthognatha , sp. ii. 



AA. Falces without exterual spur. 



B. Stridulatiiig-orgainvith only three large 



bristles upon tlie suture on coxa i. . . dulcicola, sp. n. 

 BB. Stridulating-organ with more than 

 seven bristles upon the suture on 

 coxa i. 

 C. Stridulating-organ with some short 

 stout spines on the anterior side of 

 coxa i. amongst the stridulating 

 bristles (median anterior eyes larger 

 than laterals). 



Ann. <i- Mug. N. Wist. Scr. 9. Vol viii. 22 



