734 OBSERVATIONS ON SOME AUSTRALIAN POLYCH/ETA, 



Syllis corruscans. N. sp. 

 (Plate L., figs. 1—3 ; and LV., fig. 5.) 



The colour of this large species is rich greenish-brown on the 

 dorsal surface (after preservation in alcohol, sage green) ; red on 

 the parapodia and the cirri, and reddish green on the under surface. 

 There are two broad bands of emerald green on the first three 

 segments, running obliquely backwards and outwards and narrow- 

 ing posteriorly. The head and palpi are bright crimson. 



The length is usually about 3| inches, the greatest breadth J of 

 an inch. There are 150 to 200 segments; on an average the 

 segments are about four times as broad as long. In the anterior 

 portion of the body the breadth of the segments is about seven 

 times the length ; towards the middle of the length of the body 

 it is about five times, the breadth of the body decreasing and the 

 length of the segments increasing at the same time. Each of the 

 segments of the middle and posterior regions of the body is 

 marked on the dorsal surface with several impressed transverse 

 lines. 



The head is short, twice as broad as long ; the palpi are broad 

 and somewhat dorso-ventrally compressed ; they are continuous 

 with one another for a short distance at the base, rather longer 

 than the head, and are habitually directed downwards ; the praes- 

 tomial tentacles are subequal, the mesial very slightly longer 

 than the lateral, a little longer than the palpi, obscurely 

 ringed. The anterior pair of eyes are pyriform, with the 

 apex directed inwards and slightly backwards. The hinder 

 pair are rounded, situated behind and internal to the first, 

 close to the posterior border of the head. There are two 

 subequal peristomial tentacles which are much shorter than those 

 of the prsestomium, and, like them, indistinctly ringed. The 

 dorsal cirri are longer than the tentacles, usually about equal in 

 length to the breadth of the body (some being a little longer, 

 some a little shorter), not very distinctly ringed. The number of 

 joints varies from ten to twenty ; in some instances a considerable 



