ba ENTOZOA OF MARINE FISHES OF NEW ENGLAND. 459 
to be much narrower than the first joint, with curved regular outlines, 
except at the posterior edge, where there is a shallow notch. The front 
of the head is bluntly conical, expanding quickly, then moderately cor- 
tracted, making a kind of knob or button at the apex; this knob is 
nearly circular. Measurements showed that the lateral diameter was but 
little greater than the marginal. Inthe larger specimens this convexity 
of the bothria had entirely disappeared, the thin membrane having col- 
lapsed and the typical foss:e of the Dibothrie make their appearance. In 
the larger specimens, also, the bothria are much shorter in proportion to 
their width than in the smaller specimens (Fig. 7). The first segments 
are distinct, length as great or even greater than the width, triangular. 
The median and posterior segments are much crowded, width as much 
as or even more than ten times the length, alternately long and short, 
Sometimes roughened by transverse wrinkles toward the posterior end. 
Posterior end bluntly rounded (Fig. 8). 
The following measurements are from alcoholic specimens: 


Dimensions. No. 1. | No. 2. | No. 3. | No. 4. 
mm. | num. min, mn. 
Length of strobile ...-.....-..- Regn dcemnbdeodeedccsucecbotesodsarde se 55.00 | 67.00 | 94.00 |........ 
J) SEP ETL) (OE SEN Le es ee Te ee eS ternigh: Cee aecmroaree rt O3GO0 eemaeetat 0. 64 0. 64 
Diameterot head; lateral apex. 2. --\5-6 2202.5 jcewccweew ea ectemecsans 0.34 0, 25 0. 33 0. 34 
Piameter of head, marcinallapex -----2----\-----< --05 2-06-seenaces-- 0. 30 0. 25 0. 83 0. 34 
ipresdthy ot bothrigm, widesb part: ....2----- 4)... 5-.2.-.25-225--5--02 0.42} 0.40 0. 52 0. 54 
Greatest marginal diameter of head.-..-.-.-- Saisie] OF 46.) ct tenn aeeie eters | tee tette 
Lateral diameter of first segment.-....-.- 0 





Marginal diameter of first segment....--- 2 -| 0.34 40,'| 525, dace leas eeteials 
Length of first sezment.-.......---..------ eee , QRS) | eee 02: 40) Sages: 
Greatest width of strobile ...........-.----..- aot ERO. 1. 60 TSO} |osasecee 
Average length of segments near posterior By Gal (Spare OS DN Seem ste 
Men entnOt POSLELION SOPMONG on Kno) oo alam oe nie ome wie win eomesini sie = O20" 22 2 as2—n) eee eee 
BECAOLDOLPOSLOLlOr SOCMENO.:2sce% cos2s abscess ons eelcde ede cceeecassc 1400 | PS e ae 0:40) We sacmene 


It will be seen upon comparing Figs. 6 and 7 that there is great va- 
riety of form to be found in the bothria of these worms. Other forms 
could be given, but it is believed that those chosen for illustration are 
sufficiently typical to prevent mistakes in identification. In many 
specimens the convex outline of the bothria is lost, while the other pro- 
portions of Figs. 5 and 6 are preserved. In cases where care is not 
taken the preserving fluid may distort the bothria. 
I did not observe any indication of the hooks on the head, mentioned 
by Wagener for D. microcephalum (Entwickelung der Cestoden, p. 69, 
tab. vii, figs. 77 and 77a). The resemblance of this worm to Wage- 
ner’s figure is sufficiently close to indicate a probable identity. The 
close relationship of the hosts, Orthagoriscus mola and Alutera Schepjii, 
does not lessen this probability. 
In the absence of positive proof of such identity, which can be ob- 
tained only by observing some other stages of development, I think it 
best to classify this worm as a new species with the provisional name 
D. alutere. 
