238 Dr. W. B. Benham on an 
to be one species at different ages, for in the smaller of the 
two the clitellum was undeveloped, whereas the larger—which 
is the subject of the present communication—was evidently 
mature. Being of this opinion, I cut the smaller worm into 
a series of sagittal sections and proceeded to dissect the 
larger; more recently, however, having had the leisure in 
which to examine these sections, I find that the former 
presents several important differences from the larger dissected 
one, and certain peculiar characters, which, at the moment, I 
have not time to discuss, so that I must leave the worm 
unidentified for the present. 
Of the genus Lhinodrilus, Perrier, we at present know 
three species, all from the neotropical region, viz. R. para- 
doxus, Perrier *, from Caracas, in Venezuela, 2. Gulielmus, 
Beddard f, from British Guiana, and &. Tenkatec, Horst f, 
from Surinam; the new species, which has affinities with 
both the latter, was collected at Cayambe, in Ecuador, at a 
height of 14,000 feet. 
Ithinodrilus ecuadortensis, sp. n.§, 
is 3 inches (7°5 centim.) in length, and consists of some one 
hundred somites. It is thus smaller than any of the previous 
species, though R. Tenkated approaches it most nearly, being 
11°5 centim. in length. 
The colour of the preserved specimen is perbaps worth 
recording, though no doubt very different in life; when 
stripped of its cuticle it was dirty olive-green, the clitellum 
buff, tending to orange laterally, the tubercula pubertatis 
being of a deeper brownish tint. 
The chete, as in the other species, are in four couples on 
each somite, the inner couples being very close to the middle 
(ventral) line; if this space be taken as the unit (s), the 
distance between the outer and inner couples is 14s. In &. 
Tenkated this lateral interspace is less than the ventral space, 
and in L, Gulielmus it is equal to twice the ventral space. 
The cheetee are absent from the second as well as from the 
* “Rech. pour servir ete. Lombric. terrestres,” Nouv. Arch. d. Mus. 
d’Hist. Nat. de Paris, viii. 1872, p. 65. 
t “On the Structure of a new Genus of Lumbricidee (Thamnodrilus),” 
Proc. Zool. Soc, 1887, p. 154. Mr. Beddard has recently recognized the 
characteristic features of Rhinodrilus in this worm, to which genus he 
now refers the species (Quart. Journ. Micr. Sci. xxxi. p. 159, footnote). 
{ “ Descriptions of Karthworms,” Notes from the Leyden Museum, ix. 
p- 101. 
§ In a strictly etymological sense perhaps “ @quatorius” would have 
been preferable. 
