HALID AY AND LOEW 
59 
environs of St. Petersburg, and I had no difficulty in ascertaining 
that a female Tipula with abortive wings, which occurred abun¬ 
dantly in the same localities, was its female. At the same time I 
recognized this female in the Tipula dispar Hal. ( Entomological 
Mag.j 1832-1838, p. 155), and communicated this identification to 
Winnertz, who informed Walker of it. As this happened before 
1856, Walker published in his “Ins. Brit. Dipt.,” Vol. Ill, p. 342 
(1856) at bottom, in the Errata, the following note: “ Pag ana 
Meig. Syn. dispar Hal. — On the authority of Count Osten 
Sacken, communicated by Winnertz.” There is no doubt that 
Haliday’s communication to Loew was based upon this passage. 
Considering all the services rendered by Haliday to Loew, it 
would have been the latter’s duty to publish a detailed appreciative 
obituary notice of Haliday’s life and especially of his work, after his 
death in 1870. Nobody was better fitted for such a task than Loew; 
nevertheless, he did nothing of the kind. 
It was probably at the request of Loew that Haliday in his letters com¬ 
municated to him a series of remarks on the contents of the first volume of 
the “ Monographs of North American Diptera ” (1862). I reproduce here some 
of these remarks, with the comments necessary for a proper understanding of 
them. 
(1) To “Monographs,” I, p. 24, Thereuidae. Haliday says: “Why not 
Therevidae 1 Tliereva ? It is simply a mistake of Agassiz (“ Nomenclator ”) to cite 
Thereua as Latreille’s original form; and, if it had been so, analogy would 
require the correction in v ” (Haliday). 
In my “ Catalogue North Amer. Diptera,” 1878, p. 96, and also p. 239, Note 
168, I have likewise protested against Loew’s Thereua ; nevertheless Loew con¬ 
tinued to use it to the very last, without giving any reason for it. I shall insert 
here, once for all, the result of my investigation of this matter. Loew has The- 
reva in his “ Posener Dipteren” (1840). Thereua appears for the first time in 
the Stett. Ent. Zeit., 1844, p. 126, 127 (passim), in an article on the Leptid 
Baryphora. It must have.been suggested to Loew by Agassiz’s “ Nomenclator” in 
manuscript, of which the part on Diptera had passed through his hands (as 
is proved by the words on the titlepage : recognovit Loew). The printed 
text cannot have been in Loew’s hands in 1844, because it contains references 
to Eclimus Loew, Haemasson Loew, both of 1844, Nygmatodes Loew, Posthon 
Loew, both of 1845. These references were evidently added by Loew himself 
in the manuscript. But, after Loew, a philologist overhauled the “ Nomen¬ 
clator,” and this gave rise to Loew’s complaint in the Berl. Ent. Zeit., 1868, 
p. 382, and 1876, p. 209, that he had spoiled his Eclimus , derived from eWiyos 
(famished), and not from eK\tiy.ybs (quod restat). As to Thereua, Loew agreed with 
the philologist, the more so as Bouchd, in his “Naturgesch. der Insecten,” p. 45, 
