19 
2. Ascaris LavisstmA. (Annulosa, Pl. XXX. fig. 1.) 
Ascaris levissima, Baird, Cat. Entoz. Brit. Mus. 25. 
Head small, in form of a narrow circular rim; valves of mouth 
large and distinct, of a triangular shape, divided at the tip into two 
lobes, each of which again is broadly emarginate. Between each of 
the valves, at their base, is a small smooth tubercle or prominence. 
Body round, very smooth, of a rather dark olive colour, marked with 
numerous very fine smooth longitudinal les, and occasional very 
distinct red circular lines at irregular distances ; tapering at both ex- 
tremities, narrower at posterior extremity. Qn each side of the body 
is a smooth narrow band of a lighter colour, which runs the whole 
length, and has the appearance at first sight of a wing, but is not 
raised. Length 10 inches; greatest breadth 4 lines. 
Hab. ? India; from the Collection of General Hardwicke. 
Brit. Mus. 
3. ASCARIS BIFARIA. 
Ascaris bifaria, Baird, Cat. Entoz. Brit. Mus. 26. t. 1. f. 2. 
Head rather small; valves rounded, wrinkled transversely and 
slightly bifid at the upper margin. Body round, much narrower at 
anterior than posterior extremity. Anterior third of body surrounded 
with numerous very close-set, circular, raised strie. Remainder of 
body smooth, with the strize not raised and about one-fourth of a line 
apart from each other, till within about half an inch of inferior ex- 
tremity, which is large and obtuse, when it again becomes surrounded 
with numerous raised circular lines or striee which give it a wrinkled 
appearance. The tail terminates in a papilla, and the anus is lunar- 
shaped and situate at the base of the papilla about half a line from 
the extremity. The whole surface, in addition to the raised lines or 
strie, is covered with exceedingly fine and immensely numerous 
striee. A line runs down each side of the body throughout its whole 
length. Length 9 inches, breadth 5 lines. 
Hab. ? From Korea. Collected by Capt. Sir E. Belcher, C.B. 
Brit. Mus. 
Family Gorpi1pz. 
Genus Merits. 
1. MERMIS SPIRALIS. 
Mermis spiralis, Baird, Cat. Entoz. Brit. Mus. 35. t. 1. f. 3. 
About 7 inches in length and } mill. in breadth ; of a red colour, 
rigid and twisted into many spiral convolutions. Anterior and poste- 
rior extremities obtuse. Body of equal size throughout and quite 
smooth. 
Hab. Abdomen of a species of Grasshopper from Rio Janeiro. 
Brit. Mus. 
2. Mermis rigipus. (Annulosa, Pl. XXX. fig. 2.) 
Mermis rigidus, Baird, Cat. Entoz. Brit. Mus. 35. 
Body of a light amber colour, smooth and very shining, narrow 
at upper extremity, very soon becoming thicker and terminating at 
