478 '\Yii. S. Marshall and N. C. Gilbert, 



Caecliieola x)arvulus n, </. /*. sp. 



Small distomes (Fig. 1), 0,45 mm X 0^5 mm, elliptical in outline, 

 tlie anterior end somewhat flattened, the posterior bluntly pointed. 

 Body entirely covered witli minute spines arrang^ed in two series of 

 diagonal rows over entire body. Moutli terminal, oral sucker larg-e ; 

 acetabulum much smaller than oral sucker, situated in median line 

 on ventral surface slightlj^ anterior to center; praepliarynx and 

 Oesophagus ciuite long-, of nearlj^ equal leng'th and width; pliarynx 

 well developed; intestinal caeca wide, nearly equal in length to 

 praepharynx, pliarynx, and Oesophagus combined. Excretory vesicle 

 Yshaped, the median stem about one-third the length of entire 

 AYorm, the lateral branches extending forward beyond the pharynx. 

 Genital pore median, within anterior margin of acetabulum. Testes 

 are two very large ovoid bodies in posterior half of body, obliquelj" 

 behind one another; copulatory apparatus absent; vesicula seminis, 

 large and double. Ovary trilobed, at anterior edge of the festes on 

 or slightly to right of median line; yolk-glands lateral, far forward 

 in body ; Uterus of a descending and an ascending brauch, extending 

 to near posterior end of body ; receptaculum seminis dorsal to ovary. 

 In caecal tubes and stomach of the wide-mouth black bass, Micro- 

 pterus salmoides. 



This small Trematode was generally found in the caecal tubes 

 of the host which part of the alimentary traet would always, in an 

 infected fish, contain more of the parasites than anj" other part. 

 They were also found in the stomach and upper part of the intestine. 

 The fluke was not noticeable for frequent occurrence but for the 

 great number present in the few infected fish. The parasites could 

 just be Seen without a lens, appearing as small, dark specks sus- 

 pended in the fluid which filled the caecal tubes. 



OsBORN (6) describes a new genus of fluke found in the stomach 

 and intestine of the black bass from New York and Michigan. His 

 description and figures at first led us to believe that we had found 

 specimens of the parasite he had described. Osboex says of this 

 new fluke, Cryptogonimus chili, "the worms appear to the naked eye 

 as extremely minute black spots in the yellowish chyle of the host" 

 and he then gives their length as from 0,525 mm to 9,3 mm. The 

 first measurement would correspond very closely to our specimen,. 

 the second, would not and we should hold this to be a mis-print, a 

 worm üf this length surely appearing larger than "a minute black 



