256 CALIFORNIA ACADEMY OF SCIENCES. 



The inner couple of the setje in somite xvii, close to 

 the male pore, is generally lull, though in some specimens 

 there was onl}^ one seta. The pair in xviii is also present. 



A most important characteristic of the species is a con- 

 necting secondary vessel in somite ix. In other species, 

 except O. Hendriei, so far known, the two pair of hearts 

 in somites x and xi are the only four secondary vessels 

 which connect the dorsal and ventral vessels. But in 

 O . limicola we find one pair of large vessels in the poste- 

 rior part of somite ix, just behind the diverticulum, which 

 connects the two main vessels. This connecting pair is 

 c^'lindrical of almost even width, and evidently does not 

 pulsate, or pulsates only weakly, judging from its appear- 

 ance in preserved specimens (fig. 31, c. z\). 



In size Ocnerodrilus limicola stands between O. 

 Beddardi and O . agricola. It is decidedly smaller than 

 agricola, especially as regards the part anterior to the 

 clitellum. Too much importance must not be placed on 

 the size of any of the species, as they vary considerably, 

 and the smaller individuals are equally sexually developed 

 as the larger specimens. 



Habitat. This worm I found in a clear running mill- 

 race and pond at El Portal, a hacienda close to Antigua 

 Guatemala, in Guatemala, Central America. It appears 

 to be strictly a water species as I did not find it in the 

 drier soil outside of the pond. All the other species 

 hitherto known either live both in water and in drier soil, 

 or in soil only, and must be considered as semi-aquatic 

 or terrestrial. 



Ocnerodrilus Eiseni Beddard. 



This worm lately described by Beddard differs, accord- 

 ing to that author, from the other species as regards the 

 following points : Clitelluin extends from somites xiii to 



