﻿4 ARKIV FÖR ZOOLOC4I. BAND 4. N:0 19. 



From those species I liave identified the following, kiridly 

 sent me by Mr. Krone: 



Typhlohagrus kronei, noh. 



Pimelodella transitoria, noh. 



Rhamdia sebae (Cuv. & Val.) 



Glaiiidium albescens, Liitk. 



Xenocara stigmatica, (Eigenm. & Eigenm.) 



Loricaria Urna, Kner. 



» latir ostris, Boul. 



Hemipsilichthys duseni, noh. 

 Plecostomus commersoni, Cuv. & Val. 



» agna, noh. 



Corydoras kronei, noh. 

 CallicJithys ccelatus, Cuv. & Val. 

 Leporinus frederici, (Bl.) 

 Gohiomorus maculatus (Gunther) 

 Carapus fasciatus (Pallas). 



Now, from the great number of fishes, only the first 

 could live in the caves, as Mr. Krone has stated. 



It is evidently a natural selection of a very striking 

 manner, and the fact of the exemplar bearing an eye may 

 also prove how persistent the inheritance is, and that the last 

 is able to spring in any one descendant of an evolved form, 

 after many generations, amidst other creatures normal to the 

 new kind of life. 



Unfortunately, the preserving fluid in which the abnor- 

 mal specimen had been laid, did not permit me to inquire into 

 the degree of perfection of the organs; nor did Mr. Krone give 

 me any information aboiit its possible visual power. The 

 fishermen of Iporanga, as Mr. Krone tells me, gave to 

 Pimelodella transit07'ia the ancestral paternity of Typhlohagrus 

 kronei. 



The two forms are, indeed, very much alike, and, if it was 

 not for the absence of the eyes the two must be taken as one, 

 the other characters being unimportant ones. As there is in the 

 Iporanga River no other form more closely allied, the second 

 must be evolved from the first, and the fishermen of Iporanga 

 are not wronir. 



