OBITUARY. 287 



and to refer to the original authorities ; and on the whole we can 

 heartily congratulate the author on the production of a very 

 useful and meritorious work. 



OBITUARY. 



Arnold Forster (or Foerster, his earlier use) died at Aix-la- 

 Chapelle, on August 13th last, at the age of 74. He was horn there 

 on January 21st, 1810, educated at the public school there, soon 

 to return as "Lehrer," in April, 1836, " Oberlehrer " in April, 

 1850; and in 1855 became entitled to "Prof. Dr. Foerster," an 

 acknowledgment of his entomological studies from his country 

 and from his university. He entered the University of Bonn in 

 1832, and, entomologically speaking, his own words now become 

 of interest to all hymenopterists. In 1868 he wrote, — " In Nees 

 von Esenbeck's rich collection, which I became acqainted with 

 at Bonn, I obtained the first suggestion — as it were the first 

 bias — to a study which presented a new world full of unexplained 

 phenomena. Here I also learnt, as I still keep in lively and 

 thankful remembrance, to know the main generic types of 

 the different orders of insects ; the knowledge of which could 

 indeed only be attained to through autopsy, or with great 

 exertions, from the deficient literature of that early period. 

 The Neesian collection first gave my studies a fixed direction and 

 determination. This author's ' Hymenopterorum Ichnemnon- 

 ibus affinium Monographic ' treats of the first three tribes of the 

 parasitic hymenoptera, — the Chalcidiclas, Proctotrupidae, and the 

 Braconidas, — the study of which I have eagerly pursued through- 

 out." And so it is, for Forster has been a most voluminous 

 writer on the parasitic Hymenoptera since 1841, when his 

 monograph of the ' Pteromalinen ' appeared. Since then we 

 have had most elaborate — too elaborate — monographs of Pezo- 

 machus (1850 — 1), Campoplex (1868), Hyl&us (Prosopis) (1871), 

 Plectiscus (1871), and Stilpnus (1876), published in Wiegmann's 

 ' Archiv,' the ' Bheinland,' and the ' Vienna Verhandlungen.' 

 When we find one species, Gravenhorst's Exolytus Icevigatus, 

 divided into 57 species of females and 136 of males, it is natural 

 to feel somewhat alarmed (see Verb. ver. Kheinl. xxxiii., 47 — 118). 

 His various papers on the Tenthredinidse, Proctotrupidae and 

 Chalcididae in various serials, and his three " Centurien " of new 



