
No. 426.] NWEMERTEAN. PARASITES OF CRABS. 439 
embryos which swim away and which do not chance to find 
another suitable crab probably perish. The observations of 
the European writers mentioned above 
are mainly in accord with the account 
as here given. 
The mature worms often become 
25 mm. or more in length, are generally 
bright reddish orange in color, but some 
are reddish ocher and others brick red. 
Their anatomical details agree closely 
with such descriptions of the European 
species as have been given, although 
these descriptions refer mainly to the 
external features. McIntosh’s colored 
drawing (Pl. I, Fig. 5) of the worm, his 
figures of the anterior portion of the 
body and of the proboscis, as well as 
his detailed description of these parts, 
agree in most respects with the New 
England form, except that I find the 
posterior, glandular portion of the pro- 
boscis (Figs. 2—4, 6) much shorter than 
McIntosh represents. Yet it seems 
highly probable that such differences as 
appear to exist are largely accidental, 
and that the New England form is 
specifically identical with Kolliker's 
Nemertes carcinophilos. Joubin (93) eant dose ds Mid 
also gives a colored figure of the worm moved from the worm. ac, mc, 
H x : č i fe, anterior, posterior, and middle 
as it lies folded in its mucous sheath  ‘Gambers respectively; z, gland 

i cells; e, canal connecting anterior 
TE the egg decus of the crab. and middle chambers; fs, rem- 
In internal organization the worms © nants of proboscis sheath attached 
: A a o terio: ber; t connec- 
agree closely with a second species which- ripen da vd eir due 
I found abundantly on the gills of another berisimbedóed ; 4, “basis of central 
vow x 300. ; 
species of crab (Epialtus productus) at 
Monterey, California, and which is described in detail below: 
. Both the Atlantic and the Pacific forms show such wide 
deviations from all other species of the genus Eunemertes, in 
