PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 389 
of Coryphella than with that of any of the related genera. It was orig- 
inally referred to Cuthona on account of the lateral expansions of the 
head. .The odontophore is remarkably high and narrow; the central 
teeth are dark brown, large, strong, with the median point very large, 
compressed, and curved forward, projecting far beyond the small, sharp, 
lateral denticles, of which there are usually eight or nine on each side; 
lateral teeth thin, pale, comparatively small, narrow, acute, without any 
denticles, or rarely with some very small ones near the base, which is 
rounded and but little expanded. 
This species occurs from Massachusetts Bay to Halifax, Nova Scotia, 
and from low-water to 50 fathoms. 
Facelina Bostoniensis (Couthouy) Verrill & Emerton. 
This species has been very much misunderstood, and totally different 
species* have often been confounded with it. It is, however, very 
easily distinguished from all of our other species. It is the only known 
species from the New England coast that has the dorsal tentacles dis- 
tinctly laminated or plicated. 
It is a true Facelina, having only a single row of teeth, with the cen- 
tral denticle prominent. 
It is common from above low-water to 20 fathoms, on Obelia and other 
hydroids, from Massachusetts Bay to Block Island and Newport, R. I. 
This season it occurred abundantly among Obelia geniculata, on Lami- 
naria, off Block Island, in 18 to 20 fathoms, associated with large num- 
bers of Lamellidoris muricata. 
This species is very closely related to the European species, Facelina 
Drummondii (Thomp., 1843) and F. elegans (Alder & Hancock). 
Facelina pilata (Gould) Verrill & Emerton. 
Inits dentition this species agrees closely with the preceding, having 
but a single row of teeth, of nearly the same form. It should be 
referred properly to Facelina, although it does not agree strictly with 
the diagnoses of that genus, especially in respect to the lamination of 
the dorsal tentacles, which are, in this species, nearly smooth. This 
character is, however, variable in this genus, the laminw being very 
prominent in F. coronata, rudimentary in F. elegans, and absent in 
F. pilata. 
Cratena Veronice Verrill, sp. nov. 
Size moderate, about 25"" in length, rather stout. Dorsal papille 
cylindrical, obtuse, moderately slender, arranged in twelve to fifteen 
regular transverse series on each side, the middle ones containing eight 
to ten or more papilla; anterior groups smaller, situated well forward, 
*The species described by Bergh (Anat. Bid. til Kundskab.om olidierne, p. 102, 
pl. 5 a, 1864) under the name of Coryphella Bostoniensis is entirely distinct. It has 
three rows of teeth, and is closely related to Coryphella Mananensis Verrill (Stimpson 
sp.), common on our northern coasts. 
