of tlie Virginian Coast. 21 
SPH^ROSILLIS apd. 
Sph^rosyllis fortuita n. sp. 
PL. IV. FIGS. 44-48. 
Head oval, slightly convex, length to breadth as 1 to 2 
(f. 44). Eyes four, large, oval ; anterior pair at posterior 
third of the head, lateral; posterior pair just within and 
but little back of the anterior. 
Antennae fusiform, equal, two-thirds as long as head 
and palpi taken together. The unpaired antenna originates 
between the posterior eyes ; the lateral just in front of the 
anterior eyes. The palpi are large, rounded externally, 
bluntly rounded in front, united along their inner two- 
thirds, outer third free, but not diverging. There is a 
wide and deep depression between the palpi, extending 
from the head to the free portion. 
First segment narrow, but perfectly distinct from the 
head. 
Tentacular cirri similar in all respects to the antennae. 
Dorsal cirri, a trifle shorter than the antennae, and not 
quite so much enlarged at base, especially on the posterior 
segments. 
The anal cirri are double the length of the dorsal cirri, 
constricted at base ; their diameter increases slightly along 
their inner half, when they are somewhat suddenly con- 
stricted, the outer half having about one-half the greatest 
diameter of the basal half (f. 45). 
Ventral cirri, arise from base of feet, delicate, cylindrical, 
in front as long as the feet, longer behind and turned back- 
ward on a few of the posterior segments. 
Feet very stout, cylindrical, bilabiate. The oesophagus 
reaches to the middle of the 5th segment. The stomach 
barely reaches into the 7th. The oesophagus has a cov- 
4 
