Male Organs 117 



able distance, and is again bent backward to find its 

 outlet in the last segment. A dilatation in the first part 

 of its course is frequently seen to be filled with sperm- 

 filaments ; the walls are glandular, at least in the late 

 larva and pupa, and perhaps in the fly also. Fig. 88 

 shows sections through the bight of the ejaculatory duct 

 in the late larva, where each section exhibits a double 

 tube lined with long cylinder epithelium. Many insects 

 exhibit paired accessory glands, contributing a glutinous 

 secretion to the spermatic fluid. In Chironomus, how- 

 ever, the same product appears to be secreted by the 

 glandular wall of the duct itself. The wall of the duct 

 has a delicate coat of transverse muscles. 



Fig. 8S. — Sections across the bight of the ejaeailatory duct (see line in fig. 102), 

 from larva. 



The external male parts are described on p. 105. 



Oscar von Grrimm (1870) has described the liberation 

 of unfertilized eggs, capable of development, from a pair 

 of genital orifices situated on the eighth abdominal 

 segment of the pupa of a small species of Chironomus. 

 Confirmation of this observation is much to be desired ^ 

 Many examples of parthenogenesis in insects have been 

 recorded, and Cecidomyia (Miastor) is known to be 

 capable of parthenogenetic and viviparous reproduction 

 as a larva. 



' We have not found the ventral apertures of Grimm, but note tliat a 

 pair of transparent rounded bodies, the spermathecae, lie exactly in the 

 same place, and are seen through the skin of a female pupa. 



