122 DESCRIPTION OF THE PLATES. 



PLATE VI. Fig. 12. Is a figure of the natural size of one of the large 

 claws of Pagurus Bernhardus, shortly after it 

 has burst from its containing cyst. 

 Fig. 13. Enlarged view of Fig. 11. 



Fig. 14. One of the large claws of Carcinus Mcenas still 

 enclosed within the eyst. From observations 

 made, it appears that these young legs remain 

 within the cyst until their own covering or shell 

 is of sufficient strength to act as a means of 

 defence. They do not obtain a true shell for 

 some time after the cyst has burst. 



Fig. 15. Raw surface of proximal extremity of leg in Can- 

 cer Pagurus, shortly after the animal has thrown 

 off the distal portion. This figure is made for 

 the purpose of shewing the distribution of the 

 peculiar vessels, and their mode of running from 

 the circumference towards the circular vessel in 

 the centre. 

 Fig. 16. Longitudinal section of young leg still within the 



cyst. 

 a a Part of old leg containing the reproductive 



organ. 

 b I External cells. 



c Smaller nucleated cells. 

 d d Cyst of young leg. 

 e Femur of young leg. 

 / First tibial joint of young leg. 

 g Second tibial joint. 

 h Tarsal joint. 



Fig. 17. Natural size of young leg. 



Fig. 18. Portion of blind extremity of one of the peculiar 

 vessels which are attached to the blood-vessel 

 running to the leg, Plate ix. Fig. 14. The con- 

 tents are oil globules, but in the figure have 

 somewhat the appearance of nucleated cells. 

 Fig. 19. An enlarged view, for the purpose of showing 



the connection of these vessels. 

 Fig. 20. Two of the blind extremities from raw surface of 



leg, where they present a clavate appearance. 

 Fig. 21. View of the extremity, shewing the dark spot 

 supposed to be a germinal spot. 



