318 Dr. O'Bryen Bellingham on Irish Entozoa. 



lation, in which is the orifice of a duct leading to the ovary. The 

 latter organ occupies the middle of each articulation, and consists 

 of a central canal, which is often filled with ova, and of branches 

 proceeding from its sides. In addition, a slender dark-coloured 

 body is seen, which extends from the marginal orifice inwards 

 towards the centre of the articulation, where it ends in a small 

 oval vesicle ; this is considered to be the male organ by which 

 the ova, as they pass through the marginal orifices, are impreg- 

 nated. 



The organs of locomotion in the Tcenia consist of transverse 

 and longitudinal layers of muscular fibres ; the latter are not con- 

 tinued from one articulation to another, as in the genus Bothrio- 

 cephalus, in consequence of which the articulations are readily 

 detached, and each joint when separated from the others enjoys 

 some power of motion. No distinct organs of circulation exist in 

 the Tcenia, and nothing like a distinct nervous system has yet 

 been observed in them. 



Rudolphi has arranged the species of this genus in two great 

 divisions : in one the head is armed with a circle of very minute 

 recurved hooks ; in the other this part is naked or unarmed. The 

 latter are further subdivided as the head is provided with a ros- 

 tellum or prominence in front, or as this is absent. 



A. Inermes. 

 a. Capite simplici, non rostellato. 



, f Tcenia expansa ...... . . \ Small intestine of sheep (Ovis 



\ ovina (Linn., Turt.) J Aries). 



n m • .- * * f Small intestine of rabbit (Lepus 



2.T<emapechmta* ( Cuniculus). 



* The Tcenia pectinata is included in Turton's list of British species, 

 and is very well named, as its serrated margins present the appear- 

 ance of a comb. I have found it in the wild rabbit upwards of 18 

 inches in length. Its colour before being immersed in spirits of wine 

 is reddish ; the head is not small (as Rudolphi describes it), but is 

 larger in proportion than that of the Tcenia lanceolata, to which it 

 has some general resemblance. The oscula are round and directed 

 forwards ; the articulations nearest the head are very short ; they gra- 

 dually increase in length, but all are broader than long ; the posterior 

 articulations are very thick and have somewhat a fleshy appearance. 

 The marginal orifices are best seen in the articulations near the head ; 

 they are opposite, and a short filament projects from each, which as- 

 sists in giving the margin the pectinated appearance ; in the most 

 posterior articulations the filaments do not project. The ova are 

 exceedingly numerous, globular, and of a white colour ; they are so 

 minute as to be scarcely distinguishable with the naked eye. 



