New Forms of the Hemichordata. 173 



middle, but none occurred between the two last-mentioned yellow 

 streaks. No distinct circular furrow was seen in this region in the 

 living animal. 



In one living specimen, which happened to have the lip of the 

 collar widely expanded, the two legs of the skeleton were seen lying 

 at an angle of about 50° to each other. In the apex of the angle was 

 observed what appeared to be a small opening — apparently that of 

 the " notochord." 



Genital Wings. — These were well developed both in length and 

 breadth. Their greatest breadth was at the posterior end of the 

 gills. It was, when spread out, a little over twice the length of the 

 proboscis. The posterior extremity could not be exactly determined, 

 as from this point they gradually diminish in size and lie alongside 

 the hepatic coeca as mere ridges. The place of transition from 

 distinct folds to ridges is about the middle of the hepatic coeca. 

 Here also the brilliantly coloured gonads ended in most specimens. 

 There was, however, no abrupt transition, as in some other species. 

 The free edge of the genital wings are always in contact with each 

 other where they join the collar. They are transparent throughout, 

 in marked contrast to the gonads. Towards the body they meet 

 each other above the intestine behind the gills, and this region is 

 also clear and transparent. A line genital streak (apertures of the 

 gonads) occurs along the centre of each, and is of a dark reddish 

 colour, the colour of the gonads themselves being a bright yellow. 

 The genital folds usually met each other dorsally over the body, 

 though often folded outwards, so as to expose the gills; their point of 

 origin is the dorso-lateral region of the body. 



Gills. — The gill region is comparatively small, being equal to the 

 combined length of the proboscis and collar. This length did not 

 vary in any of the specimens examined. In breadth it was fairly 

 uniform till near the posterior end, when it abruptly tapered off to a 

 point and was often observed to pass under the joined bases of the 

 genital pleurae, about one-seventh of its total length being thus 

 hidden. At its widest anterior part it was about half the length of 

 the proboscis. About fifty gill-slits or pores were counted in the 

 deep furrow at each side of the gill. In the living animal the 

 anterior of these were slit-like, being more than twice as long as 

 broad. Towards the posterior part of the gill they became more 

 circular, and the most posterior were almost circular, sometimes 

 square. In preserved specimens all the openings were decidedly 

 elongate. 



Hepatic Coeca. — These are about sixty in number, and are arranged 

 in pairs. Anteriorly they are less definite and more widely set 



