* Note on the Classification of the Annelides.” 101 
work upon this class, that of M. Grube, is dated as far back as 
1851; and numerous investigations have since come to enrich 
our knowledge of the group; the work of the French savant 
will therefore fill a sensible gap in our zoological literature. At 
present we only possess an insufficient summary of this impor- 
tant work. The book is in the press, and its author has pub- 
lished in advance the table of the orders, families, and genera 
adopted by him, in order, as he himself says, to elicit from his 
confréres some observations of which he may be able to make use. 
This kind of appeal to the public authorizes us to present, 
without any previous apology, some remarks on the classifi- 
cation of M. de Quatrefages, even before the publication of the 
work announced by him. ‘This publication will, no doubt, 
nullify some of our criticisms; but others will perhaps be sus- 
tained, or even find favour with the illustrious academician, 
As in 1859, the author continues to eliminate from the class 
of Annelides the Hirudinea, the Gephyrea, and the Oligocheta 
(Erythrémes, Quatref.). This elimination, made at a time when 
other authors are endeavouring, on the contrary, to place the 
Gephyrea among the Annelides, from which they have been so 
long excluded, appears to be justifiable for, at least, a portion of 
these animals, but can hardly be extended to the Olgocheta. 
These worms are certainly true Annelides, and differ much less 
from most of the families left in the class by M. Quatrefages 
than Phoronis, Wright (Crepina, Ben.) ; and yet the author 
assigns this singular form a place among the Serpulacea. 
The reason, moreover, which leads M. Quatrefages to exclude 
the Oligocheta from the class of Annelides is of comparatively 
little weight. This naturalist distinguishes im the division 
Vermes two series of classes—one dieecious, the other monee- 
cious. The moncecious classes are the Oligocheia, the Bdeilea, 
the Turbellaria, and the Cestoidea; the dicecious classes are the 
Annelida, the Rotatoria, the Gephyrea, the Malacobdellea, the 
Myocelea, and the Nematoda. Now the character of androgyny, 
or of the separation of the sexes, is a secondary character, which 
cannot serve for the distinction of classes. Several genera of 
Serpulacea include moncecious species, and M. Quatrefages does 
not any the less on this account assign them a place among his 
dicecious Annelides. Nor does he exclude the hermaphrodite 
Nematoda from his dicecious class Nematoda any more than the 
dicecious Planarie from his moneecious class Turbellaria, or cer- 
tain dicecious Cestode worms from his moneecious class Cestoida. 
At every step in other divisions of the animal kingdom we find 
moneecia and dicecia side by side in the same class, the same 
family, and sometimes in the same genus. We therefore do not 
hesitate to think that M. Quatrefages attaches too much impor- 
