Phoridae. 87 



many species, otherwise not indoor forms, may occur in this way, 

 thus my friend Dr. Th. Mortensen, who lives in a villa at a wood 

 and to whom I am indebted for very valuable aid in coUecting Phorids 

 to me, one summer caiight all the specimens occurring on his windows, 

 and in this way he took no less than some sixty species. As mentioned 

 above many foreign forms occur with ants or termites, and to these 

 many aberrant forms, with apterous or semiapterous females and 

 also otherwise curious belong, The species of the African genus Wan- 

 dolleckia occur epizoically on large land-snails {Achatina\ running 

 about on the snails probably feeding on the slime, 



The Phorids have only rather recently been studied more closely. 

 In 1901 Becker pubhshed his well known monograph; in this work 

 all the known species were well treated and many synonymicai 

 questions were elucidated by the study of types; but the author had 

 no large material. From 1906 to 1912 Wood then pubhshed a series 

 of articles on the family in Ent. Month. Mag. and by his work the 

 knowledge, especially of the smaller forms (Aphiochaeta) made a large 

 step forwards. For the first time the important character of the meso- 

 pleura being bristly or not (detected by Collin) was used here and 

 was of very great consequence; Wood's tables included about 146 

 species and of these about 100 were new, but of the total number 

 114 belong to Aphiochaeta, 94 of these being new. Malloch much 

 advanced the study by dividing the old genus Phora into several good 

 genera, and he and Brues have made a great work with foreign forms, 

 especially in the American fauna. Pater H. Schmitz S. J., the well 

 known specialist in Phorids, has in a series of papers done a most 

 splendid and careful work with foreign forms, especially myrmeco- 

 philous and termitophilous species, and since 1918 he is publishing 

 an elaborate work on the European fauna, of this work four parts are 

 pubhshed, but it is still unfinished, most species of Aphiochaeta 

 remaining. I beg here to offer my thanks to this latter author for 

 the very valuable aid he has yielded me during my work both by 

 sending me rich material and in other ways. 



The number of European species is at present about 335; in 

 Brues' catalogue from 1914 (Bull. Wisc. Nat. Hist. Soc. XII) about 

 530 species from the world are enumerated (besides some fossil and a 

 number under "incertae sedis"), but a large number of both European 

 and non-European species has been described since then which I 

 have loosely estimated to about 160, so that the total number of 

 species from the world is at present about 700. How large the increase 



