i39U DR. F. K. BEUUARD OX 



this brief account of difierences, to be hard to reconcile with 

 specific identity. The account given by Pai'ona of internal 

 structure is so slight that the comparison cannot be pursued 

 further. 



A question of nomenclature thus arises. The name Tcmia 

 struthionis first occurs in Rudolphi's " Sj'nopsis '' *, it is there a 

 iiomeii nudum, but given on the authority of Houttuyn in 

 Miiller's edition of Linnteus f. In the earlier woi-k of Rudolplii J 

 the same worm (I piresume) is named Tcenia struthiocavieli, and 

 is also a nomen nuchtm, and again referred to Houttuyn in 

 Miiller's Linnfeus §. I am indebted to Mr. 0. Davies Sherborn 

 for kindly informing me that Houttuyn himself || does not i-efer 

 to the ostrich at all in his work, though T?enias are mentioned. 

 It is thus ei'roneous to term the species Tcenia struthionis or 

 Tcenia strvthiocaineli Houttuyn. 



In Miiller's work there is no name given at all ; the occiiiTence 

 of a Tcenia in the ostrich being merely mentioned. Thus if a 

 nomen nudum has any claim at all to be admitted, the species is 

 to be' referred to Eudolphi and is to be called Tcenia struthio- 

 ccimeli, since the earlier of the two works by that author which 

 mention the species calls it by that name. Diesing ^, how^- 

 ever, quoting both Miiller and Rudolphi's two works, terms the 

 species Tcenia struthionis, but again as a nomen midtim. The 

 earliest actual description therefore of a Tcenich from Struthio is 

 that of Parona already referred to. We may perhaps safely 

 accept his name, since it is accompanied by a description though 

 not a conclusive one. I shall have to return again to this matter 

 in considering the species to which it seems necessary to refer 

 the worms which I now desciibe. „ 



The scolex of the worm which forms the subject of the present 

 communication is a. little over 1 mm. in breadth in the two or 

 three examples in which I measured it. The region of greatest 

 breadth is opposite to the suckers ; but the breadth was not 

 increased by the extrusion of the latter. The suckers lay within 

 the contour of the scolex. It is clear therefore that this species 

 has a less robust scolex than Parona's Tcenia struthionis. But 

 while the actual measurements of the scolex of my species agree 

 more with those of the M'orms described by v. Linstow as Tcenia 

 struthionis, my species shows a scolex with a well-developed 

 rostellum, thus disagreeing with v. Linstow's worms and so far 

 agreeing with that described by Parona. This is very evident 

 from the figure given by Parona **, where the hardly extruded 

 rostellum is plainly exhibited. Parona does not state the number 



* Entoz. Sjn. Mant. 1819, p. 173. 



t Linne s NatuvffeschicLte von P. L. S. Miillev, Th. vi. Bd. ii. p. 904. 



X Entoz. Hist. Fat. 1810, p. 209. 



§ It is to be noted that the initials of Miiller are as stated here. He is referred 

 o as " St. Miiller " by Rudolphi, and " H. Miiller" hy Diesing. 



II Natnurlyke Hist'orie, vol. i. pt. 14, 1770. 



*![ Systenia Helniinthuni. i. 1850, p. 555. 

 ** Parona, loe. cit. pi. \ i. fig. 2. 



