LOEW AS A DIPTEROLOGIST 
125 
As this letter of Haliday, dated November 22, 1856, was closely followed by 
Loew’s monographic publication on European Dolichopodidae in the “ Neue 
Beitrage,” Vol. V, 1857, it would appear that Loew in this case was under the 
influence of Haliday. However, the same letter of Haliday contains a scheme of a 
distribution of Dolichopodidae into sections, in the synoptic table of which the 
pubescence or bareness of the first joint of the antennae plays an important part, 
but is not the basis for a primary subdivision, as it is in Loew’s table. • 
This collection of letters will probably afford an abundant material to the future 
student for the investigation of the influence upon each other of the two eminent 
dipterologists in the classification of the Dolichopodidae , but such an investigation 
is entirely beyond my competence. 
In the Empidae (in the broadest sense), Loew, so far as I can 
judge, has done excellent descriptive work, both for Europe and 
for North America. But, in the “Monographs of North American 
Diptera,” Vol. I, 1862, he committed a mistake in not following 
Haliday (“ British Entomology. Diptera,” Vol. 1,1851), and in not 
uniting into a single family the Hybotidae , Tackydromidae, and Em¬ 
pidae. I have already alluded to this subject, above, on p. 49, in 
the Chapter VII (“ Historical and critical remarks,” etc.) in which 
I have introduced some criticisms of the generally unsatisfactory 
classification of the Diptera OrthorrkapJia in that volume of the 
“ Monographs.” 
In working up the North American Syrphidae , Loew, to use his 
own expression (in lUteris ) “ stuck in a jungle of uncertainty ” in 
attempting to disentangle the existing descriptions of the North 
American species of Syrphus (in the narrowest sense). With more 
material at my disposal, I succeeded better in this task, and thus 
excited Loew’s astonishment to such a degree that it may have 
been the cause of the unexpected rupture of his correspondence 
with me, which was resumed only two years later. (The story of 
this curious incident has been related by me in detail in Chapter 
XII.) 
Loew, as he once admitted to me in conversation, had made but 
very little study of the Calyptrata (in Rob.-Desvoidy’s sense) and 
he therefore did not publish much about them. His papers on the 
genera llomalomyia and Azelia are praised by a specialist, Mr. P. 
Stein. This author, in his paper on “North American Ant/io- 
myiidae ” ( Berl . Ent. Zeit ., 1898), complains of Mr. E. Walker’s nu¬ 
merous descriptions and adds: “ How different, in comparison, are 
