Distinction between the Species o/Thrynus. 315 



Tarantula, Karsch { = Phrynus). 



P. reniformis, Herbst (Haiti). 



P. variegatus, Herbst (Amazons, Jamaica, Venezuela, 

 W. coast America). 



One example of P. palmatus, Herbst (Mexico) . 



P. Whitei, Gervais (Burclwan). 



P. coronatus, Butler (California). 



P. Batesit, Butler (Upper Amazons). 



P. longicorm's, Butler (Para). 



P. granulosus, Butler (South America). 



P. goi-go, Wood (Para ?) . 



P. cheiracanthus, Gervais (Demerara, New Granada). 



Our two specimens of P. pahnatus from Mexico are refer- 

 able, according to this character, to two distinct genera, 

 although in all other respects (excepting that one of them is 

 slightly immature) they agree fairly well. Now although it 

 is possible that they may be distinct, I am much more inclined 

 to believe that the character discovered by Dr. Karsch, although 

 interesting as not having previously been prominently brought 

 forward, is an unreliable one even for specific distinction. 



There is one point in which Dr. Karsch appears to have 

 misunderstood my paper where he says, "Butler's Einthei- 

 lungsgrund in amerikanische, australische, asiatische unci 

 afrikanische Formen halte ich fur durchaus unthunlich, da 

 diese geographischen Grenzen nicht fiir das, was man unter 

 Art versteht, existiren und auf die Bestimmung der Formen 

 als solche gar keine Verwendung finden." If Dr. Karsch 

 means that geographical divisions do not necessarily repre- 

 sent groups of subgeneric value, I am quite willing to agree 

 with him ; but if he means that they are of no use in enabling 

 a naturalist to identify his species, I can only answer that he 

 is the only zoological worker, with the exception of one good 

 man who has unfortunately left this world, who ever, to my 

 knowledge, attempted to make such a statement. For my part 

 I believe geography to be of the greatest value in assisting 

 the identification of species ; and I should at all times name a 

 wingless African insect, if previously wrongly identified with 

 a tropical American one, just as I have renamed the P. medius, 

 described and figured by Koch, from America, knowing by 

 intuition, as well as by comparison of specimens and figures, 

 that it could not be the P. medias of Africa. 



Before writing a paper on the subdivision of a large genus, 

 many types of which we possess, it is strange that Dr. Karsch 

 should not have asked me to examine them and tell him 

 how many joints there were in the hind tibiae of the typical 



