188 CLASS V. 



. Doubtful genera: Gyrodactylus NOKDM., Mikrogr. Beitr. 

 i. p. 195, Hectocotylus Cuv. Ann. des Sc. nat. Tom. xvm. 1829, p. 

 147, Tab. XL A, Phcenicurus RUD. (Vertumnus OTTO, Nov. Act. 

 Acad. Leop. Car. xi. 2, p. 294, Tab. XLI. fig. 1). Comp. DUJARDIN 

 Hist. Nat. des Helmintlies, pp. 480482, and 640. 



ORDER II. Ccelelmintha s. Utricularia. 



Entozoa with nutrient canal suspended in a distinct abdominal 

 cavity, supplied with mouth and anus. Sexes distinct. 



Family IV. Nemato'idea. Body round, elastic, often attenuated, 

 filiform. 



Phalanx I. Acanthotheca DIESING. Mouth inferior between 

 two pores on each side which emit a single or double booklet. 

 Body roundish or depressed, transversely annulate. 



Pentastoma RUD., Linguatula FRCELICH, LAM, 



The worms of this genus were arranged by RUDOLPHI with the 

 Trematoda, but they differ from these by their internal structure ; 

 in external form some species resemble the Cesto'idea; they form a 

 small group which ought to be separated from the proper Nemato'idea, 

 but still belongs to the Ccelelmintha. Comp. on this genus G. M. 

 DIESING Versuch einer Monographie der Gattung Pentastoma, An- 

 nalen des Wiener Museums i. 1835, s. 1 32, Tab. i. iv. 



Sp. Pentastoma tanioides RUD., Linguatula tcenioides LAM., Cuv., OWEN, 

 RUD. Entozoor.Hist. nat. Tab. xii. figs. 8 12, BREMSEK Icon. Helm. Tab. x. 

 figs. 14 16, DIESING 1. 1. Tab. in. figs, i 5, OWEN Trans, of Zool. Soc. i. 

 4. 1835, PP- 3 2 5 33- PI- 4> f- IO J 6> MIBAM, Beitrag zu einer Anatomie 

 des Pent, tcenioid. Nov. Act. Acad. Cces. Leop. Car. Tom. xvii. 1835, pp. 

 623 646, Tab. 46, Ann. des Sc. nat. 2 e se"rie, Tom. vi. 1836, Zool. p. 135, 

 PL 8 ; in the frontal sinus of the dog and the wolf, also in the larynx of 

 these animals, and, according to some observations, in the frontal sinuses 

 of the horse and the ass ; the male is four times smaller than the female, 

 which attains a length of three inches and more. 



Pentastoma moniliforme DIESING 1. 1. Tab. iv. figs, n 13 ; in the lungs 

 of the Indian serpent (Python). 



The name Pentastoma is to be rejected, because the four lateral openings 

 near the mouth are not mouths, and because by its resemblance to similar 

 names of genera of Trematoda it may easily mislead to the idea of an 

 union with this division. It is, however, so generally received, that it can 

 scarcely be altered without needless confusion. The name Linguatula of 

 FRGELICH as the older would deserve the preference, but it applies properly 



