REPRODUCTION. 



179 



The external reproductive organs of the male Cockroach are 

 concealed within the 9th sternum. The so-called penis (fig. 102) 

 is long, slender, and dilated at the end. It is not perforated, 

 and we do not understand its use, though it probably conveys 

 the semen. 



D 



Fig. 102. External Male Organs, separated. The lettering agrees with Brehm's 

 figures. A, titillator; B, penis; C F, hooks and plates. X 8. 



The " titillator ' (B runner von Wattenwyl) is a solid curved 

 hook with a hollow base. Besides these, are several odd-shaped, 

 unsymmetrical pieces (fig. 102, C, D y E, F\ moved b}^ special 

 muscles. A pair of styles (see figs. 32-3 and 103) project from 

 the hinder edge of the 9th sternum. These paired and unpaired 

 appendages are believed to open the genital pouch of the female, 

 but we do not understand their action in detail.* 



Brehm observes that the male reproductive organs of the 

 Cockroach are most nearly paralleled by those of the Mantidao. 

 A free penis occurs in all Orthoptera, except Acridiidae and 

 Phasmidse. 



The male organs of the House Cricket will be found much 

 easier to understand than those of the Cockroach. The testes 

 are of irregular, oval figure, the vasa deferentia very long, 



e Similar organs, forming a male genital armature, have been described in various 

 Insects. See Burmeister, Man. of Entomology, p. 328 (Eng. Transl.); Siebold, Anat. 

 of Invertebrates; Gosse in Linn. Trans., Ser. 2, Yol. II. (1883); Burgess on Milk-weed 

 Butterfly, Ann. Mem. Bost. Soc. Nat. Hist.; &c. 



