110 MR. H. CHARLTON BASTIAN’S MONOGRAPH 
13. D. marINUS, Dujardin. 
Hist. Nat. des Helminth. p. 231, pl. iii. fig. D. 
** Corps blanc, long de 3", large de 0125; rapport de la longueur à la largeur 94; 
stylet protractile, continué par un long tube flexible et par le canal triquètre de l'ceso. 
phage; tégument lisse. 
“ Femelle ayant la queue longue, effilée, la vulve au milieu de la longueur, et les œufs 
oblongs, longs de 077-07 ; larges de 0™™-027. 
* Je l'ai trouvé dans l'eau de mer, parmi les algues, à l'Orient." 
6. ANGUILLULA, Ehrenberg. 
Vibrio, Müller; Ascaris, Goeze; Rhabditis, Dujardin. 
GEN. Cmar. Body long, narrow, and tapering at extremities. Caudal sucker absent. 
Integument thin, presenting neither transverse nor longitudinal markings; setæ 
none (?); papillæ 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 Ehrenberg, and modifying the general terms in which he formerly 
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-called Anguillula tritici, 
which I have now placed, with other allied species, in the new genus Tylelenchus. 
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 
subsequent 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 
! Lam indebted to the kindness of Dr. Davaine for the opportunity I have 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 
2 SR imagined, at all events in England ; and this may be due in great measure to the adulteration of of 
vinegar with sulphuric acid, 
