104 M.E. Claparéde on M. de Quatrefages’s 
Mr. Stimpson, and especially the very detailed researches of M. 
Sars, have taught us that Spinther is very nearly related to 
Luphrosyne, and consequently enters the family of the Amphi- 
nomea. 
M. Quatrefages places the genus Eumenia, CErst., at the end 
(tncerte sedis) of the Phyllodocea. We can, however, scarcely 
doubt, especially after the investigations of M. Sars, that the 
natural place of this genus is in the family Arenicolea. To make 
up for this, M. Quatrefages leaves the genus Dasybranchus in the 
family Arenicolea, where Grube originally placed it, whilst he 
enumerates the genera Capitella, Blainv., and Notomastus, Sars, 
among the genera incerte sedis at the end of the Clymenea. 
Now the favour with which the family Capitellacea, formed at a 
later period by M. Grube (for the genera Capitella, Notomastus, 
and Dasybranchus), has been generally received is sufficient evi- 
dence that this family cannot be rejected without good reasons. 
We believe that there are few families of Annelides so natural 
as that of the Capitellacea. The very exceptional characters of 
the subulate sete, which are very different (in all the rows) in 
the anterior region and in the following segments, joined to a 
disappearance of the vessels as complete as in the Glycera, and 
the appearance of coloured blood-globules in the perivisceral 
cavity, are sufficient to prove the relationship of these three 
genera. The mutual affinities of these three genera are, more- 
over, manifested in a multitude of other points. When M.Qua- 
trefages removes the Dasybranchi with ventral branchic from 
the abranchiate Capitelle and Notomasti, to approximate them to 
the Arenicole with dorsal branchize, he seems to attach an ex- 
aggerated importance to the existence of branchie. One might 
remind him that he himself has found in the genus Glycere 
abranchiate species and species provided with branchiz. More- 
over dorsal branchiz into which vessels pass (Arenicola) can- 
not be the hoinologues of ventral branchiz destitute of vessels 
(Dasybranchus). 
The family to the study of which M. Quatrefages has certainly 
devoted the most care is that of the Syllidea. Who has not in 
mind his beautiful investigations on the reproduction of those 
animals? The number of new genera established in this family 
is also considerable. We may remark, however, that the cha- 
racters employed by the author are not always very certain,— 
such as the number of eye-spots, which is often variable in the 
same species. Other characters, on the contrary, are excellent ; 
thus M. Quatrefages justly groups the genera according as their 
gizzard is armed or unarmed. But, curiously enough, his appli- 
cation does not always appear to be in conformity with his prin- 
ciple. Thus several genera (Syllis, Exogone, Autolytus, Sphero- 
