170 Dr. O^Bryen Bellingham on Irish Entozoa. 



rSmall intestine of blackbird (Turdus Me- 



13. Ascaris ensicaudata <c! ^\ -' 4. ^- r • ^ ^x. x. /ti j 



I bmall intestine of missel- thrush (^lurdus 



(^ viscivoriis). 



14. nigrovenosa* Lungs oiirog (Rana temporaria). 



,- . r Intestines of herring (C/Mjoeaf/arew^'Ms). 



T •••• 1^ Intestines of salmon-trout (/Sfl/moIVM^M). 

 Ig^ angulata .. /^^^estine of fishing-frog (Lophius pisca^ 



Parte antica crassiore ; capite alato. 

 17. Ascaris vermicularis X Large intestine of man {Homo), 



18. obvelata § . . Caecum of mouse {Mus Musculus). 



19. maculosa .. Small intestine of pigeon(Co/Mm&aZ<ma). 



describe the head as having a white oblong vesicle upon each side. 

 It is extremely common in the stomach and small intestine of the 

 domestic cat. 



* The Ascaris nigrovenosa, named so from its colour, is not un- 

 frequent in the lungs of the frog (R. temporaria). This species is 

 described as being viviparous : I have not observed that it is so ; on 

 some occasions, when cut across, I have seen a number of bodies 

 resembling ova protruded, which were white and oblong, but hardly 

 visible to the naked eye. 



t The Ascaris acus from the intestine of the salmon-trout (Salmo 

 Trutta) lived in water for some days after being removed ; they are 

 an inch and upwards in length, white, slender, and very elastic ; the 

 alae of the anterior extremity are very narrow and appear to be cre- 

 nate. The tubercles of the mouth are prominent and of a moderate 

 size ; the posterior extremity is sharp and subinflected in the male ; 

 the male is shorter and slenderer than the female. 



X The Ascaris vermicularis, maw or thread-worm of English wri- 

 ters (Oxyuris vermicularis of Bremser), is the smallest species which 

 inhabits the intestinal canal of the human subject, and has been 

 known from a very remote period. It inhabits only the large intes- 

 tine : the male is extremely minute and very rare ; the female is much 

 larger in proportion, and is very common. The three tubercles which 

 surround the mouth and characterize the genus, are minute, and if 

 the specimen has been kept in spirits for some time, indistinct ; in- 

 deed Bremser, from not having been able to distinguish these parts, 

 and from the general resemblance of the animal to the Oxyuris am- 

 higim of the rabbit, has removed it from the genus Ascaris ; while 

 Rudolphi, an equally high authority, has retained it in this genus, 

 and succeeding writers have referred it to the genera Oxyuris or As- 

 caris, as they followed Rudolphi or Bremser. I have on several 

 occasions satisfied myself that it is an Ascaris, and consequently 

 Bremser was mistaken in placing it in the genus Oxyuris. 



§ The Ascaris obvelata is a rare species ; it resembles generally the 

 Ascaris vermicularis of the human subject, and like it inhabits chiefly 



