ANATOMY. 19 
eggs that I have seen, with the possible exception of those of Leuco- 
phenga varia. These structures are, however, different in number and 
shape in the different species, and afford excellent specific characters. 
They lie spread over the surface of the food when the egg is laid 
normally, and apparently keep the anterior end of the egg from sinking 
below the surface. 
The micropyle is situated in the small papilla that can be seen at 
the anterior tip of the egg. The sperm probably enters here. 
The larva emerges from the anterior end of the egg, squeezing 
through an irregular opening formed by a split in the chitinous shell 
of the egg. 
The eggs known to me may be classified as follows: 
PE MAPOLEG RIMNCLIES hos. fia ele claces tie Uda gg Wisc sielwt-selily a eyaels Chymomyza 3 
ee NCPC CMON TOME MUATIOMTG Ls 6s dln soe china Week Heb gala Woe cadet dha hele ee 2 
Oyen a ridge above; flaments'short:. :4.}!) 20). 06 fone Vc ee Re ok Scaptomyza 4 
IPRS CTI MORESO! RYO.) ):. 815 5 iideiicke i Sokal. tres pale diwtiwe wy apacd tole dae bualtre 2 Drosophila 5 
co LISELI ED SLE TUN 70127 Naa a A oe ad 6 C.. procnemis 
“SUTTONS Wa pa a ade a a eR ab a ahs fuged HER a RNA RO 4 C. amena 
EPERPIRATELCALDS RSET C82 ERT 2 ss Dah Se es Wa Ae Re NS om ade Oe caer ee S. graminum 
OL STE Sa a lee a AP See RMR ati bie Ne AE eT ae es Poa S. adusta 
INEERETOMLLEREAI Satay er are 1085) 8 ie oe Ae A ceets, Solute? aS al 1 ea ae 6 
“By US ROETASS EE ade GPUS AE RRL NP ene a ERR Ag CPCCA MRS DG 6 a 
aN PUARA CUE Os eo She) coe ecco War AG a Se ais Bae taalle Ud dicke os ee Mae A a eae nie 8 
6. Median filament slightly thicker than either of the two lateral ones....... D. quinaria 
Median filament more than twice as thick as either of the two lateral ones. . D. transversa 
7. D. affinis, D. caribbea, D. earlei,* D. melanica, D. melanogaster, D. nebulosa, D. 
obscura, D. simulans. 
8. D. busckii, D. cardini, D. funebris, D. hydet, D. immigrans, D. putrida, D. repleta, 
D. robusta, D. similis,* D. torrei, D. tripunctata,* D. virilis. 
Anterior filaments are described for the eggs of the genus Scatophaga 
(Cordylurine), but are absent in the described Calyptere, Trypetine, 
and Agromyzine. 
LARVE. 
Various drosophiline larve have been more or less thoroughly de- 
scribed by Heeger (1851), Comstock (1893), Howard (1900), Unwin 
(1907), Martelli (1910), Johannsen (1910), Banks (1912), Keilin (1915), 
and de Meijere (1916). 
According to Keilin, the larve of D. melanogaster pass through 
three stages, separated by two larval molts. As in most other cyclo- 
rhaphous Diptera, the anterior spiracles do not appear until after the 
first molt, and the cephalopharyngeal skeleton becomes larger and 
stouter at each molt. The first-stage larve have a chitinized median 
plate, dorsal to the pharynx and just behind the mouth-hooks, which 
is not present in the second or third stage larve. Keilin has seen this 
plate also in first-stage larvee of Borborine and Sepsine. 
* The eggs of these species I have not seen. The number of filaments is given on the authority 
of Dr. C. W. Metz. 
