D. Keilin 
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(b) Melinda Rob.-Desv. (1830). Characters of the genus and previous 
KNOWLEDGE OF LIFE-HISTORY. 
Characters of the genus (PI. XXII). Flat, blue coloured Hies. Feathering 
of antennae as in Calliphora. Alulae free from hairs; male genitalia small, 
withdrawn almost from sight; three post-sutural intraalar and two strong 
sternopleural bristles; claws and pulvilli in male not elongated; cheeks 
narrower than in Onesia. 
Life-history. 
According to Robineau-Desvoidy these Hies are oviparous. This statement 
is solely based upon the observation that the abdomen in the female does not 
contain larvae as does that of Onesia. 
In 1909, Pavay-Vajna stated that the larvae of M. cognata Meig. cause 
subcutaneous myiasis in the young of the White Wagtail ( Motacilla alba). 
From his note, to which I referred in detail in an earlier paper (1915a, 
pp. 95-96), I will only restate the following: 
The observations of Pavay-Vajna were made in Hungary (Olahlapad, Komi- 
tat Also-Feher) where he found a nest of M. alba containing four young birds 
upon which were pitted wounds. In one of these wounds was a Dipterous 
larva which soon pupated; the imago emerging 13 days later was identified by 
Kertesch as Onesia cognata Meig. All the young birds died within one to 
four days after this observation. 
In 1917, Father Schmitz, in the course of his research upon Drilus fiavescens, 
frequently noticed the appearance of adult flies of Melinda cognata Meig. in the 
breeding vessels containing livingsnails (Hygromyia hispidah ., Patula rotundata 
Muller, Hyalinia cellaria and others) collected as food for the larvae of the 
beetle. On May 28th he collected, near Maastricht, a dozen living snails, and, 
on June 4th, one of these ( Patula rotundata) died, and from it there emerged 
a larva which duly pupated. From this pupa on June 25th-26th emerged an 
imago, which was identified by Dr Villeneuve as Melinda cognata, Meig. 
According to Schmitz, the observation of Pavay-Vajna is based upon an 
error in the identification of the Insect. This opinion is also expressed in the 
letters which I have received from Drs Villeneuve and Bequaert. As the 
identification of Pavay-Vajna’s specimen was made by Dr Kertesch, I would 
hesitate before doubting its correctness, but regarding Schmitz’s observation 
we may consider the occurrence of M. cognata on Motacilla alba as merely 
accidental. 
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