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 whicli at least 

 some of the muscles are attached, while others seem attached to the cells themselves. 

 Besides these epidermal arcifoi'm muscles, there are numerous crelomic arciform 

 muscles, which also penetrate the glandular layers and serve to connect the two sides 

 of the clitellum on either side of the tubercula pubertatis (fig. 138). While the 

 arciform muscles of the epidermal layer have been described by Cerfontaine in Lum- 

 bricus, the}' 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. 



QSso2')hn (JUS 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 Sj). Benhami, covering as they do both tubular and sacculated intestine. 

 Another point is the absence of a continuous blood-sinus. A continuou-s blood-sinus 

 in the sacculated intestine has been described by Benham in Sp. tmneaix, by Smith in 

 tip. Eiseni and is also found in tip. Benhnmi, 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. 



Spermathecce (fig. loO). The most characteristic feature of tijiarganophi/us 

 timithi is the occurrence of numerous spermathecte in at least three somites, while in 

 one somite there is found only one pair. Seven adult specimens from Laguna Puerca 

 were opened and agreed in the following arrangement and number of spermathecse: 



Somite vi: 2 spermathecie, in front of or slightly dor.sal to set* 3 and 4. 



Somites vii, viii, ix: 8 spermathecse in each, in front of, slightly dorsal and 

 lateral of setas 3 and 4. 



The location of the.se .spermathecse is not strictly constant as in some specimens, 

 as well as in some somites of the same specimen, the spermathecte were shoved a little 

 dorsally or ventrally of sette 3 and 4. One specimen possessed three spermathecaj 

 on one side and four on the other side in the same somite, but all the other specimens 

 possessed eight spermathecse in each of the somites, except in vi where invariably 

 only one pair was found. 



These spermathecifi 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 coelom 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 iu the, somite. 

 I believe there is no other case known in oligochneta where so many and so large 

 spermathec* are known to occupy the same somite. The size of the respective sperm- 



