158 CALIFORNIA ACADEMY OF SCIENCES. 
the center of the tubercle. The most interesting feature, however, consists in the 
presence of three or four arciform muscular bands which connect the opposite sides 
of the tubercular projection, and which, of course, serve to further push out the tip 
of the tubercle, or to relax it, as the occasion may demand. These bands are entirely 
confined to the clitellar cell layer, and penetrate to the very cuticle, to which at least 
some of the muscles are attached, while others seem attached to the cells themselves. 
Besides these epidermal arciform muscles, there are numerous colomic arciform 
muscles, which also penetrate the glandular layers and serve to connect the two sides 
of the clitellam on either side of the tubercula pubertatis (fig. 188). While the 
arciform muscles of the epidermal layer have been described by Cerfontaine in Lum- 
bricus, they are by no means known from many species. Their presence varies con- 
siderably in different species of Sparganophilus, but they are especially numerous 
and strong in this one. 
(Hsophagus and intestine. As regards the general shape of the alimentary canal 
I can see no marked difference in the various species so far examined. Again as to 
structure I find two points worthy of mention. The chloragogen cells which are 
everywhere covering the intestine are much larger and more numerous in this species 
than in Sp. Lenhami, covering as they do both tubular and sacculated intestine. 
Another point is the absence of a continuous blood-sinus. A continuous blood-sinus 
in the sacculated intestine has been described by Benham in Sp. tamesis, by Smith in 
Sp. Hiseni and is also found in Sp. Benhami, as will be recorded further on. In this 
species, Sp. Smithi, the sinus is not quite continuous, the respective blood lacunes are 
quite close and in places run together, but they are nowhere continuous in the same 
way as in the species referred to above. The sacculated intestine commences in xiii. 
Spermathece (fig. 150). The most characteristic feature of Sparganophilus 
Smithi is the occurrence of numerous spermathece in at least three somites, while in 
one somite there is found only one pair. Sevenadult specimens from Laguna Puerea 
were opened and agreed in the following arrangement and number of spermathecz: 
Somite yi: 2 spermathece, in front of or slightly dorsal to setee 3 and 4. 
Somites vil, vill, ix: 8 spermathec in each, in front of, slightly dorsal and 
lateral of sete 3 and 4. 
The location of these spermathece is not strictly constant asin some specimens, 
as well as insome somites of the same specimen, the spermathecx were shoved a little 
dorsally or ventrally of sete 3 and 4. One specimen possessed three spermathece 
on one side and four on the other side in the same somite, but all the other specimens 
possessed eight spermathece in each of the somites, except in vi where inyariably 
only one pair was found, 
These spermathece are very large (fig. 125), tall and slender, and viewed 
in cross-sections of their body they are seen to extend from one end of the ccelom to 
the opposite side, touching both body-walls. They are generally directed forward 
and crowding each other; they occupy nearly all of the available room in the somite. 
I believe there is no other case known in oligocheta where so many and so large 
spermathece are known to occupy the same somite. The size of the respective sperm- 
