Germ Cells of Leptinotarsa Signaticollis. 



141 



sist of a median vagina with a somewhat funnel-shaped oviduct 

 on either side. To the broad distal ends of each oviduct are at- 

 tached from 45 to 46 ovarioles or egg tubes, which are of a type 

 common to a large number of Coleoptera. Each tube is divided 

 into three more or less distinct regions, namely; the ovariole stalk 

 (Rohrstiehl) , which is the part proximal to the oviduct, the term- 

 inal chamber (Endkammer) , in the lower part of which the egg 

 passes through its early development, and the terminal thread 

 {Eiidfaden), which is dilated at its base into a broad cap-like 



Fig. W. a, ovary; B, single ovariole represented in longitudinal section; e, egg; 

 g. c, germ cells (young ovocytes); I. m., limiting membrane; n. c, nurse cells; 

 0. St., ovariole stalk; ov., oviduct; t. t., terminal thread. 



structure marked off from the terminal chamber by a definite 

 membrane (Fig. W.). In the terminal chamber are found three 

 different kinds of cells, the egg cells in the lower proximal region, 

 the nurse cells occupying the distal part (|) of the chamber, and 

 the epithelial cells scattered between those of the other two groups. 

 In seeking for a stage at which to begin this account, I found the 

 close of the larval period to be the most advantageous, for here 

 very simple conditions prevail which permit one to distinguish, 



