3l8 CALIFORNIA ACADEMY OF SCIENCES. 



Fig. 20. The same seen from the nuder side with the diverticula spread 

 out. 

 dvt. diverticula. 

 cl. collecting vessel. 

 Fig. 21. Diverticulum of the oesophagus, seen in cross-sections. 

 V. blood vessels. 

 ep. epithelial lining. 

 Fig. 22. Brain and ventral ganglion spread out. 

 Fig. 2.1. The genital zone more highly magnified than in fig. 3. 

 ', . male pores. 

 Iir. prostate pores. 

 '•. s. common setfe, large size. 

 f). s. penial setfe of smaller size. 



The anterior part of the body seen from the side. 

 One of the anterior prostates. 

 Anterior prostate of another specimen. 

 One of the posterior prostates. 

 *■. muscular part, 

 glandular part. 



Posterior prostate from another specimen. 

 Ciliated rosette and sperm duct and sperm-sacs in x and \i. 

 One of the posterior nephridia with peritoneal cells. 



Kerr la zonalis, tigs. 29, 30. 

 Fig. 29. The genital zone and surrounding somites withthe prostates and 

 sperm ducts seen from the inner side of the body. 



jrr. a. anterior prostates. 



I>r. p. posterior prostates. 



up. (I. sperm ducts. 



c-.-s. common setfe. 



p. s. penial setae of smaller size than the common setse. 



m. s. muscular part of the prostate. 



(jl. glandular part of the prostate. 

 Fig. 30. The inner pore of the posterior prostates. 



m. s. muscles keeping the prostates in position. 



pr. prostates. 



/>a. papilla. 



i7)tp. interiiapillary groove. 



Ocnerodrihis Beddardi, tig. 31. 

 Fig. 31. Abnormal five chambered diverticulum, seen in cross-section. 

 r. blood vessels. 

 ep. epithelial lining. 



