Notes on the derivation of winged insects through several lines etc. 



269 



Patria: Westjava, Umgebung von Buitenzorg. Type in der Kollection 

 des Herrn Prof. Dr. L. Courvoisier in Basel. 



Gerycltis courvoisieri pJiradiinon siibsp. nova. 



cf. Das weiße Gebiet der Vorderfliigel noch ausgedehnter als bei 

 der Java-Vicariante, ausgezeichnet durch einen sehr langen, zwischen 

 der hinteren und der Submediana sich hinziehenden weißen Strich. 

 Unterseits mit verminderter Weißfleckung, welche nach vorn nicht über 

 die vordere Mediana hinausgeht. 



9 dem Gerydus learchus philippus Stdgr. Q genähert, nur die 

 weiße Binde ist etwas länglicher, wodurch sich ein Anklang an gewisse 

 Q 9 von G. biggsi Dist. ergibt. Die Hinterfliigel schärfer gewinkelt als 

 bei Philippus Ötdgr. und von diesem ohne weiteres zu unterscheiden 

 durch das Fehlen der graugelben Beschuppung, welche das Discalfeld 

 aller Formen von learchus verdunkelt. 



Patria: Nord-Borneo, Waterstradt, leg., 9 West-Borneo, Sintang. 

 März 1910 (Dr. Martin leg.). 



Es ist ziemlich sicher, daß sich G. courvoiseri auch noch auf 

 Sumatra und der malajischen Halbinsel vorfindet. 



Notes on the defHvation oftvinged insects through several 

 ^ lines of descent. 



G. C. Crampton, Ph. D.* 



The erroneous idea that all winged insects are the descendents of 

 a Single type of winged insect, which in turn was derived from some 

 on^type of primitively wingless insect, has proven a serious stumbling 

 block to further progress in attempting to derive the Pterygota from 

 ancestors resembling the Apterygota. It is very difficult to understand 

 how such an idea could have arisen, for the evidence gained from 

 a comperative anatomical study of the more primitive representatives 

 of the Pterygota and Apterygota clearly points, not to o n e , but to 

 several lines to descent, in passing from the one group to the other 

 It is perhaps superfluous to add, that in speaking of the descent of 

 the l^pterygote insects from apterygote forms, it is not implied that 

 recent Pterygota are the descendents of recent Apterygota, but merely 

 that the ancestors of both groups were very intimately related, or 

 sprang from a common stock. 



The marked similarity of structure found in insects belonging 

 to the apterygote group Myrientomata and those belonging to the 

 pterygote group Platyptera (i. e. the Plecoptera and Embioidea — but 

 not the Isoptera and Corrodentia, which are included in the group 

 Platyptera by some systematists) would indicate a Community of descent 

 in these two groups. For the sake of convenience, this line of descent 

 may be spoken of as the Myriento-Platj^ptera line, and the insects 

 therein included may be referred to as the Myriento-Platyptera group. 



The great similarity in structure between the apterygote insects 

 called Dicellara (the Japyx-like forms) and insects of the pterygote 

 Order Dermaptera, clearly points to the Dicelluro-Dermaptera group as 

 representing another line of descent from the Apterygota to the Ptery- 



*) Contribution from the Entomological Laboratory of the Massachusetts 

 Agricultural College, Amherst, Mass. 



