258 . [April. 



DESCRIPTION OF A NEW BOMBYX ALLIED TO ARCTIA CAJA. 



BY DE. STAUDINGER. 



Aectia cajula, Stgr., n. sp. 



I received this pretty new species from my friend Mr. H. J. 

 Elwes, and proposed at first to have named it after him, but as it very 

 much resembles a small Arctia caja, I hope he will not object to my 

 naming it cajula. 



Mr. Elwes informed me that it was caught at a great elevation, 

 13,000 to 14,000 feet, in the North West Himalaya, in the Tibetan 

 valley of Laboul, many days' journey from any inhabited place. A 

 number of males were taken, but only one female which, to my regret, 

 is not before me whilst writing this description. 



Arctia cajula is only a little larger than the well-known European Arctia 

 aulica, L. The average length of the fore-wing is 20 mm., whereas in A. caja the 

 average length is 30 mm., and in the variety Wiskotti, Stgr., from Asia Minor, even 

 40 mm. Cajula has very much the coloration and markings of typical specimens off 

 caja. It is well known that Arctia caja is apt to show most curious aberrations^ 

 and varieties, whereas cajula appears to vary but very little. 



The anterior wings of cajula do not show as much of the white markings as ini 

 caja ; sometimes there are only from three to four irregular white spots near the base, , 

 a larger white spot in the middle of the costa, and an irregular narrow white fascia i 

 before the hinder margin. These latter marks in many specimens form an X'^il^e 

 marking as in caja. 



On the under-side the basal portion of the anterior wings is more or less red, tt 

 with some two or thi'ee black spots. \ 



The posterior wings are of a brighter red than in caja ; they show near the base t i i 

 two email black spots one above the other, there is a larger spot at the end of the > 

 median cell, and three large black spots, generally united so as to form a fascia, before i 

 the hind margin. Before the reddish-yellow cilia is a narrow black sub-marginal i 

 line, sometimes dissolved into separate spots ; this never occurs in caja, where only 

 sometimes the upper part of the cilia themselves are black. 



On the under-side of tlio posterior wings the colouring is duller, and the two 

 email black basal spots are here confluent, forming a slender fascia. 



The antennae are black, and proportionately with longer pectinations than the'i 

 white antennae of caja. The head and thorax are smoky-brown ; the palpi some- 

 times rather reddish beneath. The pro-thorax is edged with reddish-white hairs, 

 and also faintly divided with similar hairs in the middle. On the meso-thorax may \ 

 be perceived two faint reddish stripes which never occur in caja. 



The tibiae, especially the anterior pair, bear reddish hairs ; the tarsi are spotted 

 with yellow. The red abdomen is broadly ringed with black as in caja. 



Cajula cannot be a dwarf local form of caja owing to the black antennae, the 

 reddish stripes on the thorax, and the black sub-marginal line of the posterior wings, 

 &c. But on the other hand it is probably a local form of a species found on high 

 mountains in Central Asia (Russian Turkestan), by Herr Qrumm Grschimailo, for 

 which he has proposed the name of Arctia Alpherakii. 



