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typical for all other Neorhynchi is here replaced by a strikingly long 
slender organ with numerous hooks arranged upon its surface. The 
proportion of the length of the proboscis to its width is approximately 
10 : 3, as contrasted with the condition in other known species where 
the diameter and length of that organ are practically equal. However 
to the writer this disparity of proboscis form is of such a superficial 
nature that it becomes insignificant, when considering the essential cha- 
racters upon which the genus is based. Thus while the form of the 
proboscis seems to indicate the possibility of establishing a separate 
genus for this species the study of the other points in the morphology 
does not a reveal a deviation of a degree higher than purely specific 
variations such as are ordinarily included within the same genus. 
The cuticula has a uniform thickness of about 0,002 mm. The sub- 
cuticula is 0,03 —0,05 mm. in thickness. Included within this last layer 
are found the circular canals communicating with the dorsal and the 
ventral longitudinal canals. Of these canals the circular ones have a 
diameter of 0,016—0,020 mm. There are present the two layers of 
muscles in the body-wall, the longitudinal and the circular layers, which 
together form a syncitium. The muscle sheath thus formed is supplied 
with two rows of nuclei which lie one row on either side of the median 
dorsal line of the bedy. The lemnisci are large, extending almost half 
the length of the body cavity. These sac-like organs have a maximum 
diameter 0,075—0,110 mm. near the anterior end of the body and gradu- 
ally taper toward their distal ends. The proboscis receptacle has a 
length of 0,54 mm. when the proboscis is everted, and a maximum dia- 
meter of 0,11 mm. In case the proboscis is withdrawn into its recep- 
tacle the latter organ may become extended to a length of 0,87 mm. In 
the middle of the base of the receptacle, i. e. at its posterior end, is 
located the brain, a conical mass of cells whose length is 0,11 mm. and 
whose breadth is about 0,054 mm. 
The size of the testes varies considerably but the anterior one is 
constantly as large as or larger than the posterior. The former has a 
range of 0,44 X 0,14 mm. to 0,60 0,25 mm., while the latter has a 
range of 0,275 X 0,13 mm. to 0,60 X 0,25 mm. in the materials examined. 
The cement gland is characterized by the possession of sixteen large 
nuclei. It is commonly a compact mass averaging about 0,27 mm. long 
by 0,25 mm. across with an indentation of the posterior margin into 
which is received the reservoir of this gland. Occasionally, however, the 
posterior end becomes narrowed so that the reservoir lies along the 
ventral side of the gland. The cement reservoir, which in shape 
approaches the spherical, has an average length of 0,15 mm. for the 
species. The cirrus is short and conical, included between the arched 
