ASHWORTH, AN ACCOUNT OF ARENICOLA LOVENI KINBERG. 5 



ally less massive than that of A. loveni. The other sppcies 

 of Arenicola are much smaller than these; the largest known 

 examples of A. daparedii Levinsen, A. assimilis Ehlers and 

 its variety affinis Ashworth, are about 220 mm. and of A. 

 ecaudata Johnston and A. gruhii Claparéde about 250 mm. 



Colour. 



All the specimens are brown in colour, the shade varies 

 a little in different regions, being usually slightly darker in 

 the anterior portion. 



Prostomium (Plate I, Fig. 1). 



The prostomium of the type specimen is beautifully pre- 

 served. It consists of a large median lobe and two small 

 lateral lobes of almost uniform width (that is, not dilated 

 anteriorly) and united posteriorly in a narrow median portion 

 the central part of which is depressed slightly below the 

 level of the lateral portions. The transverse diameter of this 

 prostomium, at its widest part, is about 2,2 mm. 



In three of the Saldanha examples the prostomium is 

 well preserved. In each case it agrees in the form and pro- 

 portion of its parts with that of the type specimen. In the 

 Saldanha specimen in which it is best seen, the prostomium 

 has a transverse diameter of 3 mm. of which the median lobe 

 forms 1,8 mm. 



The nuchal organ is present and has the usual relation 

 to the prostomium. 



Segmeutation and Parapodia. 



This species has nineteen chaetigerous segments on each 

 of which notopodia and neuropodia are clearly seen. Each 

 of the segments from the fourth to the nineteenth inclusive 

 is subdivided into five annuli, the fourth of which — the 

 chaetigerous annulus — is the largest. Behind the third chae- 

 tigerous annulus there are, therefore, four smaller rings be- 

 tween any two successive chaetigerous ones. Between the 

 third and second chaetigerous annuli there are three rings. 



