364 DR. T. S. COBBOLD ON SOME NEW FORMS OF ENTOZOA. 



2. DiSTOMA MiNUTUM (mihi). Body flat, smooth, oblong, narrowed in front; oral sucker 

 oval, subterminal ; ventral sucker orbicular, central. Length xao^rmj ™' j breadth 

 xio-Tio in. (Figs. 4, 5.) 

 Remarks. — This exceedingly small trematode was found in great abundance in the 

 duodenum of an Oyster-catcher {Scematoptis ostrealegus, L.), and could scarcely be dis- 

 cerned with the naked eye. Its form is entirely cUfferent from JD. brevicolle described by 

 CrepUn as infesting this bird ; moreover the latter is a much larger species. The pre- 

 sence of a long uterine canal crowded with ova showed its mature character, while few 

 traces of other organs were to be seen. I did not succeed in detecting with certainty the 

 position of the genital pore, but appearances seemed to indicate its presence directly above 

 and to the right of the ventral sucker. 



3. DiSTOMA Bosci (mihi). Body subclavate, covered with minute spines, slightly com- 



pressed, thickened below ; oral sucker orbicular, subtermiaal ; genital pore above the 

 ventral acetabulum. Length \-\ in. ; breadth i^ - ^o in. (Figs. 6, 7.) 



Fasciola cohibri, Bosc, Hist. Nat. des Vers, i. p. 271, with figs. 



Distoma cohibri Amertcani, Rudolphi, Entoz. Hist. vol. ii. \i. 434 ; and Synops. p. 121 ; Diesing, Syst. 

 Helminth, vol. i. p. .398. 



Remarks. — This species has hitherto been only very briefly noticed, and is placed by 

 Diesing among doubtful and imperfectly-described forms. Like Bosc, I found several 

 specimens in the buccal cavity of an American serpent of the genus Coluber, the specific 

 name of which I am unable to give. The worm is provided with a muscular oesophageal 

 bulb, two simple digestive caeca, and largely-developed reproductive organs. 



4. BiLHARZiA MAGNA (mihi). Body smooth, linear, gradually narrowed anteriorly ; oral 



sucker oval, subterminal; ventral acetabulum round, very prominent. Length 



upwards of 1 in. (Figs. 8, 9.) 

 Remarks. — Up to the time of Bilharz's discovery of Distoma hmmatobkim, all the flukes 

 were considered hermaphrodite, and I am not aware that any other species excepting the 

 above has been since found to present a deviation from the general type. Trematodes 

 possessing so marked a structural peculiarity as D. hcematobium, associated as it is with 

 the presence of a gyuoecophoric canal in the male, deserve, I think, to be generically sepa- 

 rated from Distomata properly so called, and I have therefore employed the indefatigable 

 discoverer's name for this purpose. Only a single male example of the species here recorded 

 was observed by me, while engaged ia the dissection of a Sooty Monkey {Cercopithecus 

 fuliginosus), in some blood which had escaped from the divided portal veins. It is a much 

 larger species than Bilharzia {Distoma) hcematobia ; but its precise length I am unable 

 to record, as a portion of the caudal extremity had been accidentally removed. Unfortu- 

 nately it was at the time regarded as a common nematode ; but had its true nature been 

 earlier detected, a more careful examination of the blood-vessels would probably have 

 In'ought other individuals to light. 



