POINTS OF THE ANATOMY OP POLYXENUS LAGURDS. 35 



DESCRIPTION or PLATE III, 



Illustrating Mr. F. G. Heathcote's paper " On Some Points 

 of the Anatomy of Polyxeuus lagurus." 



Fig 1. — Part of a transverse section through the middle of the body, 

 showing the ventral plate. The bases of the legs are separated and the 

 ventral plate — that is, the fused anterior part of the two " lames pedigeres " 

 of Brandt — occupies the space between them. 



Fig. 2. — Part of a transverse section through the body, showing the female 

 external generative appendage. dil. ovid. Dilation of the oviduct. 

 ext, gen. org. External generative organ. 



Fig. 3. — Section through the male generative appendage, dil. vas. def. 

 Dilation of the vas deferens. 



Fig. 4. — Section through the sense organ. ext. cut. External cuticle. 

 hyp. Hypodermis. t. Tube. gan. Ganglion-cell. hyp. c. mass. Hypodermic 

 cell mass. 



Fig. 5. — A transverse section through the fourth segment of a female, to 

 show the ovary, receptacula seminis, and the general arrangement of the 

 organs. The figure is semi-diagrammatic; the outline of the body, the gut, 

 ovary, receptacula, and nerve-cord being from an actual section ; while the 

 heart, muscles, and fat-body are diagrammatic, g. n. c. The ganglionic part 

 of the nerve-cord. /. n. c. The fibrous part. rec. sem. Receptaculum seminis. 

 spmzoa. Spermatozoa in the receptacula. ovidct. Oviduct. 



Fig. 6. — Part of a transverse section through the posterior part of the body 

 of a female, to show the Malpighian tubes and the ovary, g. n. c. Ganglionic 

 part of nerve-cord. /. n. c. Fibrous part. fol. ov. Follicle round ovum. ov. 

 Ovum. to. ov. Wall of ovary, r. Malp. t. Returning part of the Malpighian 

 tubes. Malp. t. Malpighian tubes. 



Fig. 7. — Part of a section through the testis of a male, showing a follicle 

 containing a sperm morula. /. Follicle, sp. rror. Sperm morula. 



Fig. 8. — Part of a longitudinal section through the posterior end, to show 

 the Malpighian tubes, a. d. Anal dilatation, o. w. Outer wall of the gut. 

 malp. t. Malpighian tube. I. malp. t. Lumen of Malpighian tube. memb. 

 Membrane. 



Fig. 9. — Section through gut and Malpighian tubes, malp. t. Malpighian 

 tube. r. malp. t. Reduplicated part of Malpighian tube. memb. Membrane. 



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