ON A CASE OF COLLATERAL BUDDING IN SYLLID ANNELID. 



285 



somewhat narrowed at base and slightly tapering towards the tip. Vent- 

 ral to the paired tentacula is found a pair of subtentacula or pulpi, which 

 are dorso-ventrally slightly depressed and are bent downwards and out- 

 wards at the tip. 



Peristomium very short, being less than one-half the length of the 

 next following segment ; posteriorly and on the sides it embraces the 

 prrestomium ; on each side it bears, in the place of a parapodium, two 

 annulated cirri, of which the ventral is about two-thirds as long as the 

 dorsal one. Inferiorly the margin of the mouth forms a distinct disc divid- 

 ed more or less regularly into five lobes. Segments I — III curved so as 

 to keep parallel to the outline of the mouth. 



Parapodium (Fig. 2 A.) bears dorsally a long and annulated dorsal 

 cirrus which in general shape is somewhat fusiform owing to the slight 

 narrowing towards both base and tip. There are about 24 annuii in the 

 cirrus ; the base is provided for by a prominent process of the body-wall. 



Below it is the setigerous 

 lobe, which is moderately 

 elongate and has the infero- 

 lateral margin sloping down- 

 wards and inwards from the 

 extreme apex. This lobe is 

 furnished with about 4 aci- 

 cuke and 7 — 12, stout biarti- 

 culated setae (Fig. 2 B.); the 

 short terminal piece of the 

 setae being three-toothed. 

 Ventral to the lobe just con- 

 sidered arises a smooth vent- 

 ral cirrus, which is a somewhat tongue-shaped, laterally directed process 

 with the tip nearly reaching the lateral border of the setigerous lobe. 



The alimentary canal is of the usual form ; proboscis short and thin- 

 walled ; oesophagus moderately long, extending through the segments 

 VII — XXII, with the usual chitinous lining that anteriorly terminates in a 



Fig. 2. — A, Seventy-eigth parapodium seen from 

 the posterior side. 

 40/1 natural size. 



B, Setae from the same parapodium. 390/1. 



C, Setae from a parapodium of a sexual 



bud. 390/1. 



