Abstract
The characteristics of spermatozoon of Culex pipiens pallens, have been observed by the electron microscope. The measurment of spermatozoon is approximately 220μin length and 0.6μ in maximum diameter of the whole body. The nucleus which occupies the anterior part of a spermatozoon, is the most electron dense. The nucleus is surrounded by a ring of a row of microtubules whose axis is parallel to the long axis of the cell. The minute plate-shaped head cap located in the anterior end, is about 130Å in thickness and about 0.5μin diameter. The posterior nuclear groove is connected to the axial filament complex which extends to the posterior end of spermatozoon as axis of the tail. The flagella has a 9+1 pattern in the filament of axial filament complex. Finally, the characteristic pattern of these filaments is lost and the filaments disappear at the posterior end of the spermatozoon. The small centriole-like body abuts on the posterior end of the nucleus but in this observation no small body could be identified. Two cords of mitochondria extend along the axial filament complex from the posterior end of the centriole like body towards the posterior end of the spermatozoon.
