1208 
Journal of Agricultural Research 
Vol. XXVIII, No. 12- 
cells, as in the adult. Anterior to this region a few cells of medium size, of 
unknown significance, are found attached to the ventral border of the heart. 
The ventral diaphragm is well developed in young larvae, consisting of a sheet 
formed of transverse muscle fibers, spanning the lower portion of the body 
cavity. In old larvae, however, there remain only a few scattered muscle cells. 
The blood cells of the larva are all of one kind, of minute size and ellipsoid form. 
Many are found in division, indicating that this is the chief, if not the only, 
method of increase, since no blood-forming tissue is found. 
(12) The fat body is voluminous, occupying a large part of the body cavity.. 
Certain spaces are, however, left open for the flow of blood. The most evident 
of these are, (1) a tubular space extending longitudinally beneath the alimentary 
canal; (2) an annular space around the mid-intestine; (3) a tubular space ex¬ 
tending longitudinally above the alimentary canal; (4) a set of transverse spaces 
in the dorsal region of the body, one in the middle of each segment and commu¬ 
nicating with the ostia of the heart. Excretory (urate) cells are present in 
limited number, scattered among the fat cells. Oenocytes are very abundant 
and conspicuous because of their large size and staining reaction. They are 
found scattered throughout the trunk, but are most abundant in the abdomen. 
They are evidently amoeboid wandering cells, but no evidence of phagocytic 
activities was found. 
(13) The rudiments of ovaries in the worker larvae are very small and situ¬ 
ated in the 5th abdominal segment, attached to the ventral border of the heart 
and consisting principally of connective tissue, in which are embedded trans¬ 
verse strands of minute cells. These strands are presumably rudiments of 
ovarian tubes. Rudiments of oviducts are present as delicate solid strands of 
cells. The rudiments of ovaries in the queen larva are much larger than in the 
worker larva, showing that their development is greatly accelerated during the 
later larval stages. Their structure is similar to that of the worker larva except 
that the presumptive rudiments of ovarian tubes are both more numerous and 
longer. The rudiments of testes in the drone larva are relatively enormous r 
lying in the 4th, 5th and 6th abdominal segments, and are composed of very 
numerous transversely arranged strands of cells united by connective tissue. 
Rudiments of vasa deferentia are present. 
LITERATURE CITED 
(1) Anglas, J. 
1901. OBSERVATIONS SUR LES METAMORPHOSES INTERNES DE LA GUEPE: 
et de l’abeille. Bui. Sci. France et Belg. 34: 364-473, illus. 
(2) Bauer, V. 
1903. zur inneren metamorphose des centralnervensystems der 
insecten. Zool. Anz. 26: 655-656, illus. 
(3) Berlese, A. 
1900. CONSIDERAZIONI SULLA fagocitosi negli insetti metabolici- 
Zool. Anz. 23: 441-449. 
(4) Bishop, G. H. 
1922. cell metabolism in the insect fat-body. i. cytological 
CHANGES ACCOMPANYING GROWTH AND HISTOLYSIS OF THE FAT- 
BODY of apis mellifica. Jour. Morph. 36: 567-594, illus. 
(5) Brandt, E. 
1879. VERGLEICHEND-ANATOMISCHE UNTERSUCHUNGEN UBER DAS NERVEN— 
system der hymenopteren. Horae Soc. Ent. Ross. 15: 31-50,, 
illus. 
(6) Butschli, O. 
1870. ZUR ENTWICKLUNGSGESCHICHTE DER BIENE. Ztschr. WisS. Zool. 
20: 519-564, illus. 
