SIXTEN BOCK, TWO NEW COTYL. GEN. OF POLYCLADS. 31 



Explanation of Plates I k II. 

 Plate 1. 



Fig. 1. Chromoplana bella n. g. n. sp. 8 X. 

 » 2. Amyella lineata n. g. n. sp. 15 X- 

 » 3. Chromoplana bella. The ventral side. 

 » 4. Amyella lineata. Section of a young ovary. Zeiss Obj. 1,8 mm. 



X Oc. 2. 

 » 5. Amyella lineata. Sagittal section of genital apparatus. Zeiss Obj. 



B X Oc. 4. a. m. antrum masculinura ; s. ch. shell chamber; 



S sucker; v. s. vesicula seminalis. The dark glands are cyano- 



philoiis, the other are granular. 



Plate 2. 



All the figures, except fig. 4, have their dorsal side turned to the left side 



of the plate. 



Fig. 1. Chromoplana bella. Longitudinal (sagittal) section of the body, 

 to show the marginal sensorial furrow. The gland cells situa- 

 ted ventrally to the furrow are dark. Emptj'- cnidarian cap- 

 sules can be seen on the dorsal side above. 



Fig. 2. Amyella lineata. Sagittal section of the body. An ovary with a 

 large oocyte and the germinating layer inbedded in it. Beneath 

 the dorsal epithelium the (black-looking) pigment is visible. 



Fig. 3. Amyella lineata.' Sagittal section through the anterior end. The 

 second notch represents the transverse sensorial furrow, above 

 which ganglion cells are visible. To the extreme right is a 

 spermatophore (looking quite black). 



Fig. 4. Amyella lineata. Sagittal section through a yonger animal than 

 the one represented in Fig. 2. Ventrally to the gut-branch is 

 a young ovary. The nucleus with a large nucleolus of the 

 single large oocyte is situated more ventrally, This nucleus 

 surpasses in size any of the ovarial cells forming the germinat- 

 ing zone surrounded by the larg© oocyte. More ventrally 

 the testes are situated. Beneath the dorsal epithelium a few 

 bunnches of rhabites are visible. d. dorsal, v. ventral side. 



Fig. 5. Amyella lineata. Sagittal section through the genital apparatus of 

 a specimen other than that represented in Plate I, Fig. o. The 

 folded pharynx, the large main gut, the thick black-coloured 

 penis in the middle are clearly visible. The delicate tissue 

 between the antrum masculinum and the pharyngeal chamber 

 has burst in the section. The large black mäss to the extreme 

 right is the sperma in the seminal vesicle. Beneath the male 

 apparatus is the female apparatus and ventrally of it the 

 sucker, S. Close to the left (near Fig. 4) is the moutb, m. 



Fig. G. Amyella lineata. The photo represents the half of an ovary with 

 germinating zone and the nucleus of the large oocyte. 



Tryckt den S april 1 922. 

 Uppsala 1922. Almqvist & Wiksells Boktryckeri-A.-B. 



