112 



ged, that cannot be identihed with one of the species of this genus, already known from the 

 Indo-pacific region viz. Polyod. (Panthalis) melanonotus Gr. from the Philippines and Ceylon, 

 Polyod. (Eupompe) atistraliensis Mc. Int. from Endeavour Strait (Cape York) and Polyod. 

 (Eupompc) Grubci Kinb. from Guyaquil. Of the two first-named species we have a rather elabo- 

 rate description, biit the last one is only summarily described by Kinberg. 



The two Siboga-specimens are nearly of the same length, 14315 mm., and have a breadth 

 of aboiit 6 mm. (without bristles) ; they consist of 33 a 34 segments. Their colour is pale 

 brown, buff. The elytra leave the median dorsal region of the body bare; only the three an- 

 terior ones, that are reversed, approach each other and cover the prostomium. The scales 

 (PI. XXVIII, fig. 6) are transversely elongated, ellipsoidal, with the scar of attachment situated 

 eccentrically ; they are translucent, faintly dotted with a brown pigment and show internally a 

 oreat number of cellular cavities, giving them the appearance of a honey-comb. In P. austra- 

 liensis, according to Mr Intosh, the two pairs of anterior elytra are provided at their anterior 

 margin with a series of clavate papillae, whereas the other scales have the surface studded 

 with minute papillae. The prostomium (PI. XXVIII, figs. 4 and 5) is rounded quadrangular, 

 with two stout cylindrical ommatophores, black-coloured over a great part of their length ; be- 

 hind them two small ocular-spots are visible, like as in P. ausiraliensis and /-'. niela^ioiiotns, 

 but in P. Grubci they appear to be absent. The median antenna (tentacle) emerges with a 

 ridge-shaped basal part from the dorsal median line of the prostomium ; its terminal joint is 

 dilated below the filiform distal end and extends hardly beyond the ommatophores. In P . ausira- 

 liensis as well as in P. melanonohis the tentacle is short and does not reach the middle of the length 

 of the eye-peduncles. The lateral antennae of Pol. sihogae too have a filiform tip and are 

 a trifle shorter than the ommatophores. The palps are rather long, dotted with black spots, 

 smooth, and bent backward reach to the y''^ segment. Behind the mouth the ventral surface 

 is strongly longitudinally folded till the S'"^ segment ; with the 9''^ segment a faint transverse 

 folding commences, whereas in the median line a smooth ridge occurs, that is somewhat convex. 



The first parapodium bears two tentacular cirri, which terminate in a filiform tip and are both 

 nearly of the same length, as long as the tentacle ; it is provided with a dorsal and ventral 

 fascicle of smooth capillary bristles. The 2"<i parapodium (PI. XXVIII, fig. 7), hearing the first 

 elytrophore, shows a papilliform notopodium, provided with an acicula only; the neuropodium is 

 high, rounded, with its distal margin divided in a great number of small lobes. It is provided 

 with a large anterior lip, that has a ventral lobe that is reversed backwards ; its posterior lip is 

 much shorter. The neuropodial fascicle consists for the greater part of smooth, capillary bristles ; 

 however some of them are lanceolate, dilated above the shaft and finely denticulated, whereas 

 in the ventral part a few setae serrulatae occur. As usually the ventral cirrus is very long. 



In the 3''"^ parapodium the notopodium is somewhat longer, digitiform, whereas the neu- 

 ropodium shows but a few round lobes along its distal margin ; the capillary bristles nearly 

 all disappeared except in the dorsal part of the fascicle. However in its central part four stout 

 .spines (setae aristatae) became visible and the number of setae serrulatae increased. The ven- 

 tral cirrus is coarse, about as long as the neuropodium, with a papilliform stylode at its base. 

 To begin with the 9"' parapodium the spinning-gland occurs and in the dorsal part of the neuropodial 



& ö 



S8 



