the Larva and Pupa of the Genus Sabatinca. 449 



shows. The two genera are therefore rightly placed 

 together in the same family Micropteiygidae (s. str.). 

 Their larval type has nothing at ail in common with that 

 of the Eriocraniidae, whose larvae are leaf -miners, devoid 

 of both thoracic and abdominal legs, and with an entirely 

 different chaetotaxy. The larva of Sabatinca (and pre- 

 sumably also the full-grown larva of Micropteryx *) differs 

 from all other Lepidopterous larvae in having the compound 

 eyes still present in their normal form, instead of in the 

 degenerate form found in other Lepidopterous caterpillars, 

 where the separate eye-elements have become divided from 

 one another and are often incorrectly termed ocelli. Yet 

 other Lepidopterous larvae possess normally six of these 

 eye-elements, whereas Sabatinca has only five, the ventral 

 one being absent. This indicates that the Micropterygid 

 larval type branched off along a line of its own, from the 

 very base of the Order. We may assume that the original 

 Lepidopterous larva possessed a compound eye v;ith at 

 least six facets, in its last instav, and that the Micropterygid 

 type specialised by losing the most ventral facet and en- 

 larging the most anterior one, without any separation of 

 the six elements, whereas the remainder of the Lepidoptera 

 kept the six elements intact, but gradually distintegrated 

 the original compound eye into six tiny separate elements. 

 In the same way, the highly specialised form of the larva 

 of Sabatinca, its feeding habits, and its remarkable chaeto- 

 taxy all point to its representing an exceedingly early 

 side-line of specialisation within the Order. 



Quite different is probably the meaning of the small 

 retractile head with its three-segmented antennae, and the 

 presence of definite walking-legs of small size on all the 

 abdominal segments. All these characters are to be found 

 in the more primitive larval forms within the Order 

 Mecoptera {Chorista and Panorpa), though it should be 

 noted that the Mecopterous larvae keep the normal cater- 

 pillar form and have a chaetotaxy of normal macrotrichia 

 arranged in a manner fairly closely corresponding to the 

 typical Lepidopterous arrangement, but v.dth certain 

 small differences. In the Mecopterous larvae, also, the 

 second segment of the antenna, instead of being long and 

 slender, is large and dome-like, filled internally with an 



* The compound eyes of Micropteryx larvae are not mentioned in 

 Dr. Chapman's description {I.e., pp. 342-4), but are indicated in 

 their correct positions in his figures on Ph VI). 



