ON A CASK OF COLLATERAL BUDDING IN SVLLID ANNESLID. 



287 



4. It is elliptical in shape and consists of ig segments besides the anterior 

 eye-bearing and the posterior anal segment. The body is much flattened. 

 Its length 2.4 mm. ; and the maximum breadth at about the 8th segment, 

 I. o mm. including the parapodia. The typical parapodium consists of the 

 main setigerous lobe bearing a few setœ (represented in Fig. 2. C), 



of the dorsal annulated, and of the ventral 

 tongue-shaped, cirrus. The anteriormost seg- 

 ment bears a dorsal and a ventral pair of well- 

 developed eyes ; those of the latter are about 

 three times as large as those of the former. The 

 posteriormost segment bears a pair of long and 

 annulated anal cirri, but is lacking in parapodia. 

 The alimentary canal is the direct continuation 

 of that of the mother individual ; it is slender 

 and terminates at the anus in the anal segment. 

 An accumulation of the sexual element 

 (spermatozoa) fills up nearly the entire space 

 of the body cavity as well as its extention into 

 parapodia. The ventral nerve cord, the dorsal 

 and the ventral blood-vessels, the longitudinal 

 muscle bands and the so-called " parapodial 

 glands " are also observable. The attachment 

 of the buds to the mother individual is 

 effected by a short pedicle at the anterior 

 extremity (Fig. 4) just in front of the eye-bearing 



segment. 



After full maturity the buds will evidently separate from the asexual 

 mother individual and should become free sexual zooids ; however, it is at 

 present not certain whether or not the sexual zooid, after its detachment is 

 capable of freely swimming in water. The set.e of the sexual zooids 

 appear to be fit rather for crawling than for the natatory locomotion 

 exercised by sexual zooids of many Syllid Annelids. 

 December ist. 1905. 



Fig. 4. One of the caudal sex- 

 ual buds. Ventral view. 

 25/1 natural size. The 

 crenulations of the dorsal 

 cirri are not indicated. 



