110 MR. H. CHARLTON BASTIAN'S MONOGRAPH 



13. D. MARINUS, Dujardin. 



Hist. Nat. des Helminth, p. 231, pi. iii. fig. D. 



" Corps blanc, long de S"'"\ large de 0"'"^-125 ; rapport de la longueur ?i la largeur 24; 

 stylet protractile, continue par un long tube flexible et par le canal triquetre de roeso- 

 phage ; tegument lisse. 



" Femelle ayant la queue longue, effilee, la vulve au milieu de la longueur, et les ceufs 

 oblongs, longs de 0"""-07 ; larges de 0'"™-027. 



" Je I'ai trouve dans I'eau de mer, parmi les algues, a I'Orient." 



6. ANGUILLULA, Ebrenberg. 



Fi6no, Miiller; Ascaris, Gotze ; i?Aairf«7w, Dujardin. 



Gen. Char. Body long, narrow, and tapering at extremities. Caudal sucker absent. 

 Integument tbin, presenting neitber transverse nor longitudinal markings ; setae 

 none (?) ; papillae none (?). Pharyngeal cavity very minute. (Esophagus cylindrical, 

 with rounded swelling posteriorly containing a simple horny valvular apparatus. 

 Intestine sparingly covered with large colourless granules, presenting no appearance 

 of tessellation; distinct cells not recognizable. Vulva posterior to the middle of 

 body. Uterus unsymmetrical. Oviparous or viviparous. Spicules long, narrow, 

 curved. Accessory piece single, posterior, somewhat fan-shaped. Ventral gland 

 wanting. Floating gland-cells abundant. Lateral canals not recognizable. 

 Movements active. 



Under the old imperfectly defined genus Anguillula have been ranged, from time to 

 time by various observers, the most heterogeneous types ; but the name has become so 

 familiar, and to some extent distinctive of these free Nematoids, that I have thought it 

 better to retain it with a limited signification, than to cast it aside altogether. This 

 I have accordingly done, taking as a type Anguillula aceti, since this appears to have 

 been so regarded by Ebrenberg, and modifying the general terms in which he foi'merly 

 described the genus by the substitution of more exact statements, founded on the ana- 

 tomical characters of that species '. This will undoubtedly exclude many of the other 

 forms hitherto located in this genus, and amongst them the so-caUed Anguillula tritici, 

 which I have now placed, with other allied species, in the new genus Tyleleuchus. 

 Several of the species also that I have (from ignorance of their real characters) still 

 retained under this generic name will, I have little doubt, have to be weeded out by 

 subsequ,ent observers, and transferred to other genera as more precise information is 

 obtained concerning their anatomy. 



I have already expressed my reluctance to assent to Diesing's arrangement when he 

 places in this genus many parasitic forms found in beetles, myriapods, and other animals. 

 Some of these species, which, in his ' Systema Helminthum,' Diesing had included in the 



' I am indebted to the kindness of Dr. Davaine for tlie opportunity I liave had of examining these animals myself. 

 Before obtaining a supply from him, I had in vain endeavoured to procure them. They are much less frequent than 

 is generally imagined, at all events in England ; and this may be due in great measure to the adulteration of our 

 vinegar with sulphuric acid. 



