ANNELIDA POLYCHAETA. 173 



Like in the preceding species the length of the tenta- 

 cular cirri seems to be very variable; for usually the lou- 

 gest cirrus of the dorsal pair reaches to the 6th segment, 

 however, in some individuals it extends only to the pos- 

 terior border of the 4th ring , and in other ones it reaches 

 the 9th segment. In the males the epitocous change of 

 the feet commences at the 16th, in the females at the 

 19th ring; some segments, however, situated more in front , 

 show already marks of this transformation , f. i. a small 

 lamella at the base of the ventral cirrus at the 12th foot 

 in a male. The dorsal and ventral cirri of the anterior 

 feet have their basal portion greatly enlarged, in the males 

 this is visible at the dorsal cirrus of the anterior 7 feet, 

 but at the ventral cirrus of only 5 feet. The females show 

 this character only at the dorsal and ventral cirri of the 

 anterior 5 feet. The papillae occurring at the dorsal cir- 

 rus of the posterior segments in the males, disappear nearly 

 at the 50th segment; posteriorly the dorsal cirri are smooth 

 as in the females. 



The maxillary region of the proboscis in most of the 

 specimens has on the dorsal side a median (I) triangular 

 group of 7 teeth ; this number however decreases in some 

 of them to 4 , whereas in other individuals it increases to 

 9 or 11. Next to it on each side (II) there occurs a cur- 

 ved group of 15 to 20 teeth. On the ventral side the median 

 group (III) consists of three patches, a large transverse one 

 of about 20 teeth , arranged in 4 series , and a small group 

 ones however are not always quite isolated from the median 

 of 2 to 4 teeth at a short distance on each side; the latter 

 group. Laterally a large group (IV) occurs, consisting of 

 25 to 30 teeth. The basal region bears on the dorsal side 

 (V) a median triangular patch of 3 paragnathi ; only in 

 one of perhaps hundred specimens I observed 4 teeth in 

 this group. Laterally (VI) a short, semilunar, ridge-shaped 

 tooth occurs ; only in one specimen I observed behind the 

 ridge of the right side another small transverse tooth. 

 However sometimes one of both ridges is broken up in two 



Notes from the Leyclen Museum, "Vol. XI. 



