Tillyard. — Description of a New Dragon-fin. 345 



a pair of large basal yellow spots on each, segment from 2 to 8 ; these 

 spots are larger, squarer, and stand more closely together than do the 

 corresponding spots in U. carovei. Segments 9-10 black, a brown mark 

 low down on each side of 9, and a yellowish transverse line bordering the. 

 suture between it and 8 ; 10 with a pair of brown spots high up on the 

 sides. Appendages : Superiors broadly black, foliate, as in U. carovei ; 

 inferior shorter, subtriangular, upcurved, downy beneath, blackish brown, 

 tip very distinctly truncate, more so than in U. carovei. 



$. Slightly larger and stouter than <J ; general shape and coloration 

 closely similar to that of <$, but the upper part of the frons has the black 

 colour encroaching upon it medially as a broadly triangular blotch, and 

 the spots of the abdomen are considerably larger than in the <$. Append- 

 ages short, 1 mm., black, separated by a brownish, downy tubercle. 



Types. — S (holotype) and $ (allotype) taken together at Arthur's Pass, 

 19th January, 1920, and placed in the Cawthron Institute collection, which 

 also contains a series of paratypes from the same locality. 



Habitat. — Arthur's Pass and Cass, N.Z. 



The specimens taken at Cass had only recently emerged, and were not 

 in as good a condition for descriptive purposes as those taken a week later 

 at Arthur's Pass ; hence I have chosen the types from the latter series. 

 It should be noted that all parts described here as yellow were in life pale 

 creamy-yellow, not the rich lemon-yellow associated with mature examples 

 of U. carovei. Possibly the new species assumes the deeper yellow colouring 

 with advancing age, but we cannot be certain of this at present ; it may 

 equally well be that the creamy colour of the markings is a specific 

 character. 



Before deciding to describe this new species the specimens were taken 

 to Europe and carefully compared with the specimens of U. carovei in the 

 British Museum and in the de Selys collection at the Brussels Museum. 

 This comparison established the fact that the specimens from Arthur's Pass 

 and Cass were very distinct from any of the specimens of U. carovei in 

 these collections. Whether the differences are of true specific value, or 

 only indicate a subspecies or geographical race, it is not easy to decide ; 

 but thev are so well marked, and so constant over the whole series of forms 

 examined, that I have decided to consider them as of specific value. 



The main differences between U. carovei White and U. chiltoni n. sp 

 may be summed up as follows : — 



The two species can at once be separated by the very distinct colour- 

 patterns of the head, as may be seen from text-figs, 1 and 2. In 

 U. carovei the labrum is entirely black, and the frons has much less yellow 

 on it than in U. chiltoni ; the manner in which the black encroaches on 

 the frons both from above and below, in the case of U. carovei, is well 

 shown in text-fig. 1. It should, however, be noted that, in the case of 

 the females only, the pattern of the upper part of the frons is somewhat 

 similar in both species. 



On the thorax the dorsal bands are wider in U. chiltoni ; also, the 

 femora of this species are black, those of U. carovei being either brown or 

 yellowish. 



On the abdomen the arrangement and colour of the hairs at the base 

 is very characteristic of each species, as already shown in the description, 

 while the yellow spots in U. chiltoni are distinctly larger, squarer, and 

 closer together than those in U. carovei. The appendages are closely 

 similar in general appearance, but in the male of U. chiltoni the inferior 

 appendage is distinctly more truncate at the tip than in U. carovei. 



