After a revision of the family Limnophilidae based on material described 

 until 1955 Schmid (1955) lists 676 species for this family. 



The small families that have been established over the last decade are 

 Xiphocentronidae — 4 species (Ross, 1949; Sturm, I960), Philoreithoridae — 

 7 species, Plectrotarsidae — 3 species, Philanisidae — one species, Helico- 

 phidae — 2 species (Mosely and Kimmins, 1953), and Phryganopsychidae — 

 2 species (Wiggins, 1959). 



The increasing volume of material for investigation plus the widening s 

 scope of theoretical problems to be examined compelled entomologists con- 

 cerned with Trichoptera to renew their studies. A remarkable series of 

 works devoted to a revision of the family Limnophilidae was published by the 

 Swiss entomologist Schmid (1950 -1955) in the form of a rapid succession of 

 studies giving a critical treatment of the different genera and subfamilies and 

 a general review of the system of the family as a whole (Schmid, 1955). In- 

 stead of the formerly recognized two subfamilies, Schmid now established six: 

 Dicosmoecinae, Apataniinae, Neophylaeinae, Pseudostenophylacinae, Drusinae, 

 and Limnophilinae; the last subfamily was, for the first time in the history of 

 the system, broken down into four tribes: Limnophilini, Stenophylacini, Chae- 

 topterygini, and Chilostigmini. After a thorough critical revision and consi- 

 deration of the synonymy, Schmid, as mentioned above, established 676 species. 



Specialization found its expression also in restricting the study to stages 

 of development, e.g., larvae or adults. 

 141 Schmid studied only adult Trichoptera. His neglect of the morphology 

 of the early stages affected the value of his results. An example is the 

 revision of the tribe Baicalinini Mart. (= Thamastini Schm.) and the fact 

 that he considered the genera Baicalina Mart., Ba i c alo d e s Mart, and 

 Baicalinella Mart, as synonyms of the genus Radema Hag.; in fact, 

 these genera differ in the larvae in characters which are more important 

 than species characters, e. g., structure of the head sclerites, form of the 

 gula, chaetotactic characters, presence or absence of a horn, presence or 

 absence of gills, and form or arrangement of the gills (Bebutova, 1941; 

 Lepneva, in press). 



Winkler (l96l) wrote a detailed study of the European species of 

 Limnophilus; his keys to the species were based on adult males and 

 females; these keys are accompanied by drawings of the genitalia. 



Hickin (1942—1958) described the larvae of all species in Great Britain; 

 he included numerous drawings and in 1953 published a richly illustrated 

 popular work on all stages of development. 



Dohler (1950) published a large work on the genus Rhyacophila. He 

 divided the genus Rhyacophila into several species groups which he 

 regards as subgenera (Rhyacophila s. str., Hyperrhyacophila, 

 Pararhyacophila, Prosrhyacophila, Metarhyacophila and 

 Hyporhyacophila), based on the morphology of the larvae. 



A study of the larvae of the species Rhyacophila outside Europe 

 showed that the types of larvae of the genus are markedly more diverse than in 

 Europe. This division of the genus Rhyacophila into several species 

 groups based on the larva is very interesting; because this genus is very 

 large, however, it seems premature to consider these groups (which are 

 based on European material) as subgenera; we consider, therefore, that 

 Dohler's groups are species groups. 



Ross made a similar study of the genus Rhy a c ophi la, based on adult 

 insects. He considered the family Rhyacophilidae as consisting of 2 sub- 

 families, Rhyacophilinae and Hydrobiosinae; he excluded the subfamily 



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