1943] 
Corpus Allatum of Sheep Ked 
7 
Pratt, H. S. 
1901. The Embryonic History of Imaginal Discs in Melophagus ovinus L., 
together with an account of the Earlier Stages in the Development 
of the Insect. Proc. Boston Soc. Nat. Hist., 24:241-272. 
Thomsen, E. 
1940. Relation between Corpus allatum and Ovaries in Adult Flies (Mus- 
cidae). Nature, 145:28. 
1941. Ringdriise und Corpus allatum bei Musciden. Naturwiss., 40:605-606. 
The corpora allata of Melophagus ovinus L. Figs. 1-4 from transverse serial 
sections, 10 microns in thickness, Bodian silver impregnation. Drawn with 
camera lucida with lOx ocular and 44x objective, magnification 200 diameters. 
Figs. 5-6 drawn from dissections of flies fixed by injection with alcoholic Bouin. 
Fig. 1 . T. S. 2 mm. larva, showing relationships of corpora allata, corpus 
cardiacum tissue and other tissues of the larval head. Note the large size of 
the cells of the corpora allata. 
Fig. 2. T. S. portion of a mature larva showing huge increase in size of corpora 
allata mainly brought about by increase in cell size, which is accompanied by 
an increase in nuclear size. 
Figs. 3 and 4. T. S. head adult male and female Melophagus showing the paired 
corpora allata and their relation to other organs. 
Figs. 5 and 6. Dorsal and lateral aspects of proventriculus, aorta and suboeso- 
phageal ganglion, showing the location and anatomical relationships of the 
corpora allata. 
Description of Plate I 
Key to Abbreviations 
AO. Aorta 
C.A. Corpora allata 
C. C. Corpora cardiaca 
C. GAN. Cerebral ganglion 
D. C. Duct to crop 
FT. BDY. Fat body 
HYP. GAN. Hypocerebral ganglion 
M.G. Midgut 
MUS. Muscle fibers 
N.C.A. Nerve to corpora allata 
OES. GCsophagus 
P.N. Pericardial nephrocytes 
PROV. Proventriculus 
SAL. GL. Salivary glands 
TH. GAN. Thoracic ganglion 
TR. Trachea 
V.N.C. Ventral nerve cord 
