124 



\Vitb the exception of these abnormally situated and supernumer- 

 ary pores on the left side the external relation of the somites is 

 entirely normal. There was no evidence of split somites or 

 of a spiral metamerism in any part of the body. 



2. Male Reproductive Organs. 



Testes. 



The two pairs of testes normal to the species are found in their 

 usual positions in somites 10 and 11. In microscopical appearance 

 they are perfectly normal. Besides these there is a supernumer- 

 ary pair of testes in somite 12 (fo). These are attached to the 

 posterior face of the septum between somites 11 and 12 and present 

 the appearance of normal, well developed testes. 



Diagram showing 

 abnormal relation of 

 reproductive organs. 

 Seen from above, 

 the roofs of the 



median seminal 

 vesicles having been 

 removed, od, ovi- 

 duct, ov, super- 

 numerary ovary. 

 rs. supernumerary 

 seminal receptacle. 

 sf. supernumerary 

 seminal funnel, (s. 

 testis, vd. vas de- 

 ferens, ve. super- 

 numerary vas 

 efferens. vs. super- 

 numerary lateral 

 seminal vesicle. 



L 



Lateral Seminal Vesicles. 



On the right side of the body the lateral vesicles are normal 

 in number and appearance. 



On the left side there are three lateral vesicles but abnormally 

 situated. They take their origin in somites 10, 11 and 12 respectively, 

 the one arising in 12 being evidently supernumerary. There is no 

 trace of a lateral vesicle in somite 9 as is normally the case in this 

 species. All the vesicles on both sides were filled with developing 

 spermatozoa in different stages of division and differentiation. 



Median Seminal Vesicles or Sperm Reservoirs. 



There are normally two median vesicles in this species. In this 

 specimen there is besides these two a third posterior sperm reservoir 



