[311] When the anterior ray is double, the branches of it are called antero-anterior and latero-anterior.
[312] Identical with T. colubriformis of the sheep according to Leiper. If so, this latter name has priority.
[313] Triodontophorus belongs to the group Cylicostomeæ, which has the following bursal formula: (1) anterior cleft, (2) median double, (3) postero-external and posterior arising separately, (4) posterior double, each branch giving off two lateral branches.
[314] I.e., with a distinct space between the limbs.
[315] Strongylus (Syn.: Sclerostomum) differs slightly in its posterior ray from the other genera of the group. Each bifurcation is trifurcate rather than tridigitate.
[316] The ventral lancet (of one side) of Necator is seen in fig. [335].
[317] This also occurs in other Strongylidæ, e.g., in the genus Strongylus (Syn.: Sclerostomum).
[318] Table of Differences between Larvæ of A. duodenale AND S. stercoralis.
| A. duodenale | S. stercoralis | |||
| (1) Vestibulum oris | 1·8 µ broad | 3 µ |  | Rhabditiform. |
| (2) Genital rudiment | 3 µ to 5 µ long | 25 µ to 33 µ | ||
| (3) Thickness | Thicker | — |  | Filariform. |
| (4) Œsophagus | One-fourth body length | Half body length | ||
| (5) Tail | Pointed | Two fine points | ||
| (6) Motion | Less active than | — | ||
| (7) Gut | Soon fills with dark granules | — | ||
[319] Moults take place by the formation of a new skin below the old one, the two being in close apposition at first.