CALIFORNIA EUPRILID^. 55 



No. 2. One pair, ix/x. 



One single, xv/xvi, left side. 

 No. 3. One pair, ix/x. 



One pair, x/xi. 



One single, xiv/xv, right side. 



One pair, xv/xvi. 



One pair, xvi/xvii. 



One pair, xx/xxi. 



One pair, xxi/xxii. 

 No. 4. One pair, x/xi. 



One pair, xv/xvi. 



One pair, xix/xx. 

 No. 5. One pair, x/xi. 



One pair, xix/xx. 



The strncture of these papilhe has been referred to in connection with the 

 body-wall, and apparently does not differ in the two forms. 



Argilophilus marmoratus papillifer. 



Fig. 131, A and B. 



Argilo2)hihis jjiannomtus j^ajnllifer Eisen, Zoe, iv, 253, October, 1893. 



The ventral side of the somites with one single median row of ventral papilla^ 

 which are generally largest between the clitellar somites, diminishing gradually in 

 size toward the anterior somites. The papilla- of this form are generally, but not al- 

 ways, more oblong than in the preceding form, vvhere they are much moi-e rounded. 

 The clitellar papilla are frequently diamond-shaped (fig. 131). The papilla' vary 

 greatly in number and size in various individuals, but they are always median, never 

 paired. 8ometimes there are to 7 papilla posterior of the cliteUum. 



Ilnhltnt. This worm is very common in the vicinity of 8an Francisco Bay, 

 south of Santa Rosa, where the former form begins. I have also this form from (Santa 

 Clara County, Monterey County, Fresno County, etc. It is common in the foothills 

 of the Sierra Nevada, in Nevada County. Among many hundred specimens col- 

 lected there was only one which possessed the paired papillae of the former form. 



Systematic position. The peculiar variation of the nephridio-pores places 

 Argilophilus in undoubted proximity to Plutellus, both as described by Perrier and 

 Beuhani. The extra chatal pores in Argilophilus warrants however the forma- 

 tion of a new genus, even if no other important characteristics would help to make it 

 yet more distinct. As is well-known, Perrier's description of the ovaries, etc., in 

 Plutellus have always been considered doubtful, and by Benham have been shown to 

 be incorrect. This of course only in the case that Benham's worm really belongs to 

 the same genus as the one described by Perrier. I do not doul)t that this is so, be- 

 cause the positions assigned to the ovaries by Perrier is so abnormal that it is more 



