122 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 89 



genital pouch (B, b), and the lateral openings into a pair of lateral 

 pouches (e, e). The median pouch receives anteriorly the short ovi- 

 ductus communis (Ode), and dorsally at its anterior end the duct of 

 the spermatheca (SptD). 



The structure of the female genital apparatus in the bee has been 

 described by Zander (1916) and by Bishop (1920). Both these 

 writers apply the term " vagina" (or Scheide) to the entire passage 

 that leads posteriorly from the confluent lateral oviducts, and ap- 

 pear to imply that it corresponds with the median oviduct of other 

 insects. It is clear, however, since the spermatheca opens into the 

 anterior end of the median pouch, that this part of the exit apparatus 

 is derived from the genital chamber of the eighth segment, and that 

 only the short, narrower tube anterior to the spermathecal opening 

 is the true oviductus communis (cf. fig. 44 B with fig. 8C). The 

 shallow external triangular cavity containing the openings of the 

 three genital pouches is called the "bursa copulatrix" by Bishop; 

 but inasmuch as the common entrance cavity, the median pouch, and 

 the lateral pouches are all parts of the genital chamber and have a 

 copulatory function, the term " bursa copulatrix " should be applied 

 to these parts collectively, since they are but dififerentiations of a 

 single primitive invagination of the eighth segment, the genital cham- 

 ber. The median pouch receives the median eversible part of the 

 male organ during copulation and the lateral pouches the lateral lobes 

 (pneumophyses). Bishop distinguishes two regions in the median 

 pouch, the anterior of which contains the opening of the sperma- 

 thecal duct, but in the gross anatomy of the organ this differentiation 

 is not evident externally. Two pairs of muscles from the spiracular 

 plates of the eighth tergum are inserted on the dorsal wall of the 

 median pouch (fig. 44 B, 13, 16), and a large muscle (p) from the 

 antecosta of the seventh sternum (VIIS) is inserted on the anterior 

 wall of each lateral pouch. 



In the worker the genital organs are greatly reduced ; lateral 

 pouches of the genital chamber are scarcely perceptible, but the com- 

 mon oviduct opens into a median pouch, from the dorsal wall of 

 which arises the duct of the rudimentary spermatheca. 



The lateral oviducts of the bee, according to Zander (1916), are 

 mostly of ectodermal origin, the primitive mesodermal strands of the 

 embryo being replaced as far as the calyces during postembryonic 

 development by lateral branches of the ectodermal oviductus 

 communis. 



The valvifers of the eighth segment (fig. 40, iVlf) are entirely 

 dissociated from the rest of the segment, since they form essential 



