M. A. de Quatrefages on the Classification of the Annelides. 111 
genera among the incerte sedis, to an insufficient knowledge of the 
animals in question. I do not for a moment hesitate to admit 
the justice of this observation. When the zoological relations 
did not appear clear to me, I thought it my duty not to dissemble 
my doubts. Now this has frequently happened, as I have 
already stated, even with well-known species. In this case I have 
not placed them. With still better reason I have acted in the 
same way when it seemed to me that some important character 
was imperfectly described, or that its very existence was not per- 
fectly demonstrated. This is the case with the genus Zygolobus 
(Grube), which M. Claparéde cites as a blameable example of my 
mode of acting. With me, as with him, this genus belongs in- 
contestably to the family of the Lumbrinerea. But my learned 
critic seems not to have remarked that, from the description of 
Grube, it appears to follow that here the feet are biramose (“ Pinne 
glewaas lobis obtusis duobus, posteriore longiore, digitiformi”’). If 
this be the case, the genus Zygolubus would constitute a unique 
exception in the family, and among all the representatives of the 
Eunice type. Such a fact seems to me to require more exact 
details. Moreover Grube says nothing about the dorsal cirri, 
the presence or absence of which has served me for characterizing 
certain genera. For these two principal reasons I have left the 
genus Zygolobus among the incerte sedis, adding, “I think this 
species requires to be reexamined.” But I have placed it in the 
family Lumbrinerea, where it will certainly remain. I think that 
in this way I have acted more wisely than if I had at once ad- 
mitted the existence of a Lumbrinerean with biramose feet, 
when it may very well be that a simple transformation of one of 
the two cirri has produced the appearance indicated by Grube. 
From this example it will be seen what has been my mode of 
proceeding ; and what I have just said may excuse me from 
dwelling upon some analogous criticisms addressed to me by my 
learned confrére. 
5. A little further on, M. Claparéde says that one seems to 
remark, in my table, errors of synonymy combined with surprising 
approximations. He cites, as an example, that I have placed 
Spinther of Johnston among the incerte sedis of the family Chlo- 
remea, and Cryptonota (M. Claparéde writes Cryptonotus) of 
Stimpson also in the incerte sedis of the family Amphinomea. 
According to him, these two genera are synonymous. 
In this particular I can hardly understand the opinion put 
forth by M. Claparéde. To unite Cryptonota and Spinther in a 
single genus seems to me to be impossible. Stimpson, in cha- 
racterizing the former, speaks of its branchie, adding that they 
are undoubtedly similar to those of Euphrosyne. Johnston does 
not even mention the word branchiz, and his figures present no 
