of insect orders (Martynov, 1938: Plate l). Martynov places the time at which 

 the suborders of Trichoptera diverged in the Paleozoic; he considers each 

 suborder as an individual stem with parallel development. 



The data on the morphology and biology of Trichoptera which had 

 accumulated to the end of the 1930 's enabled M. Milne and L. Milne (1939) 

 to put forward a hypothesis on the phylogeny of the families of the order; 

 they represented this hypothesis in form of a 3 -dimensional diagram 

 (ibid., p. 540). The depth of this diagram represents the environment; the 

 oblique plane separates the smaller part (rapidly flowing water) from the 

 larger part (slowly flowing or stagnant waters). 



Following the data of Siltala on the primitiveness and specialization of 

 the larvae, Milne considers as ancestors of the order insects with a simple 

 larva resembling the larva of the recent Psychomyiidae, which live in tubular 

 tunnels at the bottom of slowly flowing streams. According to Milne, the 

 later evolution followed 2 courses which led to the development of the 

 families of Annulipalpia on the one hand, and on the other to those of the 

 Integripalpia. The development of the first group was connected with a 

 change to life in rapidly flowing streams; the development of the second 

 group was connected with a change to life in stagnant water and with an 

 154 extension of the ecological range to life in slowly flowing water. The change 

 of some forms to biotopes in rapidly flowing streams was connected with 

 abandonment of the tubes and a change to a free mode of life (like the recent 

 Rhyacophilidae). In other forms, this was connected with a shortening of 

 the tubes and a transformation of the anterior end into a capturing net 

 (as in the recent Polycentropodidae and Hydropsychidae); some of the 

 recent Annulipalpia have retained their ancient mode of life in slowly 

 flowing waters (the recent Psychomyiidae, according to Milne). 



According to Milne, the evolution of the second group, which resulted in 

 the development of the recent Integripalpia, took place on the side of the 

 "plane" of Milne's diagram which represents slowly flowing and stagnant 

 water. The first group developed into the complex Leptoceridae- 

 Odontoceridae-Molannidae-Baraeidae, which is situated most closely to 

 the oblique "plane" of the diagram; the peak of the branches or the large 

 branches of the foregoing group "penetrated through the plane" at the highest 

 stage of their evolution and became adapted to conditions which were alien 

 to their ancient nature: they shifted to rapidly flowing waters. The complex 

 of subfamilies of the family Sericostomatidae is isolated as an artificial 

 group which was established with a great amount of "stretching"; in its last 

 stage of development, this group diverged widely and the peak of its branches 

 partly penetrated beyond the "plane" into rapid waters. In an isolated 

 position at the extreme left of the diagram are situated the limnophilic 

 family Phryganeidae and the Limnophilidae, which are considered as a 

 limnophilic family. Milne's diagram is interesting systematically and 

 ecologically; the groups are arranged in sequence from the left to the right, 

 gradually moving away from life in stagnant waters (limnophilid-phryganeid 

 complex) toward life in rapidly flowing water (rhyacophilid complex); at the 

 left, stand the higher Integripalpia (Limnophilidae-Sericostomatidae) and on 

 the right, the lower Annulipalpia. 



The ecological and biological data which have accumulated clearly show 

 the error of the authors of this diagram, which is based on the ecology of the 



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