Helminth Fauna of the Dry Tortugas. 81 



relatively small and opposite; in fig. 225 they are relatively large and 

 tandem. There is also variety in the position of the ovary, it being 

 be-side the genital sucker in fig. 224 and behind it in the others. 

 Host, Sphyrcena barracuda: 



1906, July 4, 4 fish, 6 trematodes ; July 11,2 fish, i trematode, small ; 

 July 15, I fish, 7 trematodes. 



1907, July 10, I fish, 5 trematodes. 



Dimensions, life, specimen shown in fig. 225: Length 1.48; length 

 of posterior portion behind constriction 0.64; anterior sucker, length 

 o.ii, breadth 0.16; ventral sucker 0.12; breadth of body, anterior 0.16, 

 middle 0.33, posterior 0.12; ova 0.017 by o.oio. 



Dimensions of a fusiform specimen, life: Length 1.33, breadth, 

 anterior 0.07, middle 0.32, posterior o.ii; anterior sucker 0.07; ventral 

 sucker 0.06; ova 0.020 by 0.014. 



Dimensions of specimen belonging to the lot collected July 10, with 

 ova as in fig. 224a: Length 1.12; breadth 0.28; anterior sucker 0.06; 

 ventral sucker 0.04; ova 0.04 by o.oi. 



HETERACOTYLEA. 



Microcotyle incisa sp. nov. (Figs. 226-230.) 



Body proper nearly linear, greatest diameter at about its junction 

 with the sucker-bearing portion, narrowing from Infurcation of the intes- 

 tine to the bluntly rounded anterior end ; upper lip with a narrow emargi- 

 nation; anterior suckers oval-elHptical ; posterior sucker-bearing portion 

 tapering uniformly to the posterior end. The vitellaria are marginal 

 from a point a short distance back of the intestinal bifurcation to the 

 posterior end of the body proper, where the two lateral glands unite 

 behind the testes and enter for a short distance into the sucker-bearing 

 portion. The region of the vitellaria is plentifully sprinkled with small, 

 black pigment spots which continue back of the testes dorsally in 4 

 parallel rows in the median third of the width for a little less than one- 

 third the length of the sucker-bearing portion ; about 8 larger pigment 

 spots in 2 rows dorso-lateral to the esophagus. There are about 45 

 suckers in each row on the sucker-bearing portion, which portion equals 

 a little more than one-third the entire length. There appear to be about 

 24 testicules which lie in an oval cluster at the base of the body proper. 

 They are irregularly hexagonal in outline in one case, but more or less 

 rounded in others. The ovar}^ lies a short distance in front of the testes; 

 it is best seen in dorsal view, when, as in specimen sketched, it appeared 

 to be made up of a number of small lobes arranged in a wreath-like cluster. 



Host, Neoniaems griseus: 1907, July 9, 5 fish, 4 trematodes. 



1908, July I, I fish, 2 trematodes. 



Dimensions, life: Length 2.40; length of body proper 1.40; maxi- 

 mum diameter 0.42, tapering to 0.14 at each end. 



Another: Length 4.35; length of body proper 2.32; breadth, ante- 

 rior 0.16, maximum, back of middle 0.56; anterior sucker, length o.ii, 

 breadth 0.16; posterior stickers, length 0.12, breadth 0.08; ovum o.iS 

 by 0.07. 

 6 



