302 CALIFORNIA ACADEMY OF SCIENCES. 



and I supposed that a real division did not exist. Lately, 

 however, in examining a specimen of Ocnerodrihis Bcd- 

 dardi , I found that both of the two oesophageal diverticula 

 were divided, one in five chambers (fig. 20) similar to 

 those seen in cutting an orange transversely, the other in 

 four chambers. As the worm was sectioned transverseh' 

 and as I took it for granted to be an Ocnerodrihis Beddar- 

 di, I am not able to positively identify the species. It is, 

 of course, not at all impossible that some other species had 

 been collected at the same time as Ocnerodrihis Beddardi . 

 the outward appearance being very slight in the various 

 species or even genera. I am however inclined to the 

 belief that the sections were made from an abnormally 

 developed Ocnerodrihis Beddardi. Except in being 

 perfectly divided in five distinct chambers these diverti- 

 cula offered no other characteristics than those generally 

 found in this organ in the said species of Ocnerodrilus, 

 at least so far as could be judged from transversal 

 sections. Probably this chambering of the diverticula 

 is less rare than I suspect, it being only perceived in 

 transverse and not in longitudinal sections, and it is to be 

 presumed that in different specimens this internal sub- 

 division has progressed unequally. 



The diverticula in Kerria are less developed than in 

 the majority of species of Ocnerodrilus. The longi- 

 tudinal blood vessels which traverse it are less regular 

 and less numerous. The collective vessel in the distal 

 end, which is the sum of all the other vessels of this 

 organ is also narrower than in Ocnerodrilus. The whole 

 organ is shorter and more globular than in any species 

 of Ocnerodrilus so far known, and it is strongly bent, the 

 two sides touching. The exterior wall is somewhat 

 folded. It resembles most the diverticulum of Ocnero- 

 drihis occidentahs. 



