SIGALIO'NIDAE 



103 



Specific characters. There is usually a reddish brown longitudinal dorsal stripe, 

 and transverse markings more pronounced in the elytrophorous segments than in the 

 rest. Occasionally they are both absent, or one may be present and the other absent. 

 Gravier (1911, p. 81) gives a good account of the colour pattern. 



Tentacles and cirri are smooth. Prostomial peaks are very little developed. The 

 elytra are smooth except for a small patch of minute tubercles. Behind the 31st 

 chaetiger their arrangement is extremely variable, and segments with a cirrus on one 

 side and an elytron on the other are very common. 



The bristles are as described for the genus. 



Family SIGALIONIDAE 



1. No median tentacle 



— With a median tentacle ... 



2. With a dorsal cirrus on the 3rd chaetiger 



— Without a dorsal cirrus on the 3rd chaetiger 



3. Ventral bristles compound falcigers 



— Ventral bristles compound spinigers ... 



Sigalion 

 ... 2 



Psammolyce 



... 3 



. Sthenelais 



Leanira 



Genus Sigalion, Audouin and Milne-Edwards 

 Body long and vermiform. Head oval, longer than broad. There is no median 

 tentacle, and the lateral tentacles are reduced to small papillae inserted on the front 

 margin of the head. The ist chaetiger carries dorsal and ventral tentacular cirri, a pair 

 of long palps and on each side two bundles of simple bristles. There is a cirriform 

 branchia on all segments behind about the 5th. The dorsal bristles are simple and 

 denticulated. The ventral bristles are both simple and compound, the latter with short 

 and single-jointed shafts or long and multi-articulate shafts. The elytra are furnished 

 with pinnate papillae on the outer margin. 



Sigalion ovigerum, Monro (Fig. 12 a-d). 

 Monro, 1924, p. 47, figs. lo-ii. 

 Occurrence. St. 936 (New Zealand) (i). 



Specific characters. The specimen is an anterior fragment measuring 60 mm, by 

 2 mm. without the feet for 135 chaetigers. This species is chiefly characterized by the 

 absence of compound bristles with simple single-jointed blades, all the compound 

 neuropodial bristles being multi-articulate. The prostomium (Fig. 12 a) is an oval plate 

 with two pairs of minute eyes, one behind the other. There is a pair of papilliform 

 lateral tentacles lying above the ist chaetiger, and a facial tubercle on the under surface 

 of the head. The dorsal cirrus of the ist chaetiger is shorter than the head and the ventral 

 is a little longer than this. They are about one-fourth of the length of the palps. The 

 branchiae appear as slender papillae on the 3rd and 4th chaetigers and are fully de- 

 veloped by the 5th foot. The elytra are smooth and their posterior border is furnished 

 with about a dozen pinnate papillae (Fig. 12 b) with cyHndrical branches, which are 

 about 10-15 i^^ number. There is no sign of the modification of the elytra into pouches 

 containing eggs recorded in the specimen from Port Jackson. 



