178 THE entomologist's record. 



spiracle, is a tubercle with large basal plate bearing one long hair ; 

 this I take to be iv ; well below it, as far below as iv is below iii, is 

 another similar tubercle and hair ; this, from its position, is at first 

 difficult to homologise with v of other groups, but a comparison with 

 the position in Noetaid larvae leaves no doubt in my mind that it is 

 really v, in spite of its great distance beneath the spiracle. Its unusual 

 position is to a great extent explained if we consider that the trend of 

 evolution in Arctiid larvfe, like that in the Anthrocerids, is to increase 

 the girth of the segments at the expense of their length, thus causing 

 a shortening of the distance between the tubercles in a lowiitmUnal 

 direction and an increase in transverse direction, so that there is a 

 tendency in the direction of the tubercles forming a single ring round 

 each segment. Close to the spiracle, but slightly above and in front of 

 it, is a minute point that proves on close examination"" to be a very small 

 tubercle, bearing a mmute, but proportionately short, stout hair or 

 spine ; in spite of its minuteness, it is abundantly distinct from the 

 spicules. A second and exactly similar minute tubercle occurs on the 

 anterior margin of the dorsal area, slightly further from the median 

 line than is ii. The one situated dorsally on the anterior margin of 

 segment I have previously alluded to as no. 0. That in front of and 

 slightly above the plane of spiracle, might be called no. iiio, were 

 it not for the fact that Dyar has already used the term iiirt {Knt. 

 Record, vol. xi., pi. i) to signify an accessory hair situated behind the 

 spiracle on Alucitid (Pterophorid) larvre, wliich I much doubt to have 

 any relationship to the prespiracular point above referred to. It may, 

 therefore, be provisionally termed no. 00 until its exact relationship 

 has been worked out. 



2n<l imtar (specimen in formalin) : Shape and colour as before ; 

 spicules still present. Tul^ercles are still based by large flat plates, 

 but they are mox*e rounded and do not show the diamond and slash- 

 like outlines which are so marked a feature of the first skin. All 

 tubercles except i and the weak ones on meso- and metathorax that I 

 queried as iv, bear more than one hair. This, of course, does not refer 

 to the exceedingly minute ones referred to in 1st instar, which retain 

 their primitive condition throughout the larval period, and undergo no 

 change beyond slight increase in size, which appears to be somewhat 

 less than an increase strictly proportional to the size of the larva 

 would warrant. The hairs are mostly black, a few only being pale ; 

 all are long, tapering, and thorny. The dorsals on meta- and meso- 

 thorax, i + ii, are larger, and bear as many as nine hairs; iii, on 

 same segments, bears four ; beneath and posterior to it, the weak 

 tubercle (? iv) is still single-haired, and remains so in later stages ; 

 the large tubercle below and anterior to it (? v) bears five or six hairs ; 

 and there is another similar tubercle below this again ('? vii). On the 

 abdominal segments i is still only single-haired, although the plate at 

 its base is proportionally larger ; ii now forms a large wart l)earing 

 seven or eight hairs, one of which is central ; iii is still a long and 

 narrow tubercle, bearing about six hairs ; iv is also still long and 

 narrow, set somewhat obliquely, close to the lower posterior side of 

 the spiracle; some way below and only slightly anterior to it is v. 



* A lin. or ^in. objective will enable one to see it, but it requires either a no. 

 3 eje-piece added to the above or Jin. objective to make it out in detail. 



