THE ANNALS 
MAGAZINE OF NATURAL HISTORY. 
[THIRD SERIES.] 
No. 99. MARCH 1866. 
XIX.—On the Asexual Reproduction of Cecidomyide Larve, 
By Dr. R. Leuckarr*. 
{Plate I] 
Axour a year and a half ago we received, through a communi- 
cation to the Academy of St. Petersburg, the surprising intelli- 
gence that Nicolas Wagner, Professor of Zoology at Kasan, had 
observed an asexual reproduction in the larvee of a fly belonging 
to the genus Cecidomyiat. This reproduction was said to com- 
mence in autumn, to continue through the winter and spring, 
giving origin during the whole of this peried to a series of suc- 
cessive generations of larvae, until finally,in June, the last of them 
were developed into perfect and sexually mature animals. The 
flies then, as usual, after copulation, lay eggs, and thus recom- 
mence the developmental cycle just described. 
A few menths afterwards the ‘Zeitschrift fiir wissenschaftliche 
Zoologie’ (Band xi. p. 512) furnished us with a detailed memoir, 
illustrated with numerous beautiful figures, on the same subject, 
which had been sent by Wagner two years previously to the 
editors for publication, but had been kept back by them because 
the observations described in it appeared tobe “almost ineredible.” 
But this incredible has completely verified itself; and it even ap- 
pears probable, from the confirmatory observations of Meinertt in 
Copenhagen, and Pagenstecher§$ in Heidelberg, that the mode 
of reproduction discovered by Wagner is still more widely dif- 
* Translated by W. S. Dallas, F.L.S., from Wiegmann’s Archiv, 1865, 
p- 286. 
+ K.E. von Baer, “ Bericht itber eine neue von Prof. Wagner in Kasan 
an Dipteren beobachteten abweichende Propagationstorm,” Bull. Acad. 
St. Petersb. 1863, pt. vi. p. 239. (As early as 1861, however, Wagner had 
incorporated a short notice of his observations m the ‘Journal of the 
University of Kasan,’ which is published in the Russian language ; but, as 
far as | am aware, this has remained unknown out of the country.) 
t Zeitsehr. fiir wiss. Zool. Bd. xiv. p. 392. § Ibid. p. 400. 
Ann. & Mag. N. Hist. Ser.3. Vol. xvii. 11 
