Plate V. 



Fig. 43. Apex of a o-onophorc (c?) in Stylnstrr rosnis, containing- spermatocytes in process of trans- 

 forniation. 450 ,. 



— 44. Early stage in tlie development of a seminal dnct in Sfxlnsfrr iinrvegicus. 4So^/j. 



— 45. Longitudinal section through an almost full-grown, seminal duct in Sfviirsfrr rwrvrgicvs. 1^" ,. 



— 46. Median longitudinal section through a gonophore (?) with ripe o\uni in Stylastrr gi-iiniiascens. 3"° ,. 



— 47. Median longitudinal section of a gonophore (?) with ripe o\uni in S/yl'isfrr rusriis. ''" ,. 



— 48. Transverse section of a gonophore (?) near the distal end of the spadix in Stylnstrr rosnis. 'j" ,. 



— 49. Transverse section of the spadix close beneath the oxnun in Stxiastcr gci/ni/fiscri/s. '^o/j. 



— 50. Median longitudinal section through a gonophore with advanced planula larva in .S'tvt(/str/- 



