68 DESCRIPTION OF PLATES. 



Plate XII. 

 Doryphora decemlineata {Family ChrysomelidcE). 



Figs. 151-152. Equatorial plates of spermatogonia, 36 chromosomes — 35 large, i small. 



153. Fii;st spermatocyte, synizesis stage. 



154. First spermatocyte, synapsis stage. 

 155-158. First spermatocyte, spireme stages. 



159. First spermatocyte, spireme segmented and split. 

 160-163. First spermatocyte, prophases. 

 164-171. First spermatocyte, metaphase. 



172. First spermatocyte, anaphase. 

 173-174. First spermatocyte, equatorial plates. 

 175-176. First spermatocyte, late anaphase. 



177. Second spermatocyte, equatorial plates. 

 178-179. Second spermatocyte, telophase, tti, archoplasmic material. 

 180-186. Spermatids in different stages; osi, archoplasmic material from first 

 spermatocyte spindle, a^ archoplasmic material from second matu- 

 ration spindle. 



S;pruce-borers (Family Bufrestidce). 



187. First spermatocyte, metaphase. 

 188-189. First spermatocyte, equatorial plates of two species, 10 and 11 chro- 

 mosomes, 

 igo. First spermatocyte, anaphase. 



191. Second spermatocyte, equatorial plates containing 9 large chromo- 



somes and I small one. 



192. Chromosomes from prophase of the first spermatocyte, all from the 



same cyst. 



