EXPLANATION OF PLATE 53. 92 1 



Fig. 32. Section through the skin of Peripatus capensis ; it shews the secondary 

 papillae covered with minute spinous tubercles and the relation of the epidermis to 

 them. (The cuticle in the process of cutting has been torn away from the subjacent 

 cells.) The cells of the epidermis are provided with large oval nuclei, and there is a 

 deposit of pigment in the outer ends of the cells. The granules in the protoplasm of 

 the inner ends of the cells are arranged in lines, so as to give a streaked appearance. 

 (Zeiss E, oc. 2.) (From a rough drawing by Prof. Balfour.) 



c. Dermis. cu. Cuticle, ep. c. Epidermis cells, pi. Deposit of pigment in outer 

 ends of epidermis cells, s.p. Secondary papillae. 



Fig. 33. Female generative organs of Peripatus capensis, x 5. (From a rough 

 drawing by Prof. Balfour.) The following note was appended to this drawing: 

 "Ovary rather to dorsal side, lying in a central compartment of body-cavity and 

 attached to one of the longitudinal septa, dividing this from the lateral compartment 

 between the penultimate pair of legs and that next in front. The oviducts cross 

 before opening to the exterior, the right oviduct passing under the rectum and the 

 left over it. They meet by opening into a common vestibule, which in its turn opens 

 below the anus. On each side of it are a pair of short papillae (aborted feet ?)." 



F. 16, 17. Last two pairs of legs. od. Oviduct, ov. Ovary, ut. Uterus, v. c. 

 Nerve-cord. 



PLATE 53. 



Figs. 3439. Five young embryos of Peripatus capensis ; ventral view. All, 

 excepting Fig. 37, from drawings by Miss Balfour. In Figures 34 to 38 a denotes 

 what is probably the anterior extremity. 



Fig. 34, Stage A. Youngest embryo found, with slightly elongated blastopore. 



Fig. 35, Stage B. Embryo with three mesoblastic somites and elongated blasto- 

 pore. The external boundaries of the somites are not distinct. 



Fig. 36, Stage C. Embryo with five somites. The blastopore is closing in its 

 middle portion. 



Fig. 37, Stage D. The blastopore has completely closed in its middle portion, 

 and given rise to two openings, the future mouth and anus. (From a rough drawing 

 left by Professor Balfour.) (Zeiss A, Camera Oberhaus. on level of stage.) 



The following note was appended to this drawing in his handwriting : "Young 

 larva of Peripatus capensis. I could not tell for certain which was the anterior end. 

 Length, 1*34 mm." 



Fig. 38, Stage E. Embryo with about thirteen mesoblastic somites in which the 

 flexure of the hind part of the body has commenced. The remains of the original 

 blastopore are present as the mouth, placed between the second pair of mesoblastic 

 somites, and the anus placed on the concavity of the commencing flexure of the hind 

 part of the body. 



B. 59 



