. Annotationes zoologicae japonenses / Nihon do?butsugaku iho?. 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
. Annotationes zoologicae japonenses / Nihon do?butsugaku iho?. 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
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Keywords: ., bookcentury1800, bookcollectionbiod, bookdecade1890, bookyear1897
