of the Virginian Coast. 39 
the lower bundle. The branchiae are simple, and begin 
from the 10th to the 13th setigerons segment. Length, 9""". 
Number of segments, 75. 
(e.) We have next five antennae, the external in some cases 
being minute papillae, in others having attained their 
normal (relative) length. On small specimens the division 
of the head into palpi is not complete. Branchiae begin 
on any segment, from the 10th to the 23d, according to the 
size of the specimen. Eyes, always two. 
On specimens froni 10 to 20"™ in length, having more 
than 10 and less than 17 non-branchiated anterior seg- 
ments, the branchiae are usually bifurcate. 
The jaws of the youngest forms correspond perfectly 
with those of adults, save that the support (Trager) is 
relatively longer, and with a narrower posterior margin. 
In this, as in all other respects, a complete gradation can 
be established. — My figures of jaws all show four teeth 
on the large denticulated- jaw pieces (Zahne, Ehlers), as 
described by Quatrefages, instead of three, given by 
Ehlers. 
The comb-like setae of the adult are not found on the 
youngest forms. I have never seen them on specimens 
with less than three antennae, nor on those without bran- 
chiae. 
The forms under {c) will be seen to correspond very 
closely to Nematoncries oculaia Ehlers (Borstenwur7ner, p. 
371, pi. 16, figs. 19-22), while {d) is very close to Amphiro 
Knbg. (Annulata Nova Ofvers af K. Vet-Akad Fork., 1864 
p. 565 ; also Fregatien Eugenien's Resa, pi. xvii, f. 26). 
Kinberg says in his generic diagnosis: " Branchiae pect- 
inifornies vel subpectiniformes," and for the most part 
{d) has simple branchiae, but on one specimen the branchiae 
were found divided, the second division being represented 
by a small but perfectly distinct papilla. Possibly, then, 
