530 FLORENCE BUCHANAN. 



example, is the Araphinomidse, and the geuus iu which such 

 variations particularly occur is the genus Amphinome (Blv.), 

 Briig, in its widest sense, — including, therefore, the genera 

 Eurythoe and Hermodice of Kinberg and the genus Liuo- 

 p her us of Quatrefages, as well as Amphinome s. str. Knb. 



Amongst the Polychaetes collected by Professor Haddon in 

 the Torres Straits, which have been for some time, and still 

 are, in my hands for the purpose of identification, there are 

 sixteen specimens of the genus Amphinome sufficiently well 

 preserved and complete for examination with regard to the 

 point at issue. Of these fourteen belong to the sub-genus 

 Eurythoe, and six of these have each a half-segment com- 

 pletely or incompletely intercalated. The position of the 

 intercalated segments will be seen from the following table : 



Total Number Description of 



of Segments. Intercalated Half-segment. Half-segment. 



1 . 1074 . On the right side between Segments 20 and 21— Complete. 



2 . 984 . „ left „ „ 23 „ 24 



{Incomplete, 

 fused with 

 19th. 



4 . 344 . ,, „ „ » 14: ,, 15— Complete. 



5 . 344 . „ ,, „ » 11 .. 12 



6 . 88 . (23rd and 24th parapodia on the right side almost fused, 



which amounts to incomplete intercalation of a segment ou 



the left side). 

 The other two members of the genus in the collection beloug 

 to the sub-genus Linopherus, and of these one is regularly 

 segmented, while the other has two and a half of its segments 

 arranged as a spiral, beginning on the ventral and ending on 

 the dorsal surface. 



Total Number Spiral Number of 



ofSegments.i Begins. Ends. Rounds. 



7 . 1354 . On ventral surface of 75th . On dorsal surface of 77th . 24 



half-segment, left side half-segment, left side 



1 In all cases where spiral segmentation is involved the total number of 

 segments means the total number of pairs of parapodia -|- the segments (if any) 

 at the anterior end without parapodia. In the same way when a spiral is said 

 to begin (or end) on a segment x, it means that it begins (or ends) opposite 



