TYPHLOKHYNOHUS NANUS. 651 



EXPLANATION OF PLATE 35, 



Illustrating Mr, F. F. LaidlaAv's paper '^ On Typhlorliyii' 

 clius nanus. 



PiG.l. — Ty phlorhy nchus nanus, diagrammatic, seen from above, x 90. 

 Pr. Pre-oral lobe, snout, or proboscis. M. Moutb. Ph. Pliaryjix. En. Gut 

 space. .^. ^/. Anterior gut diverticulum. 5r. Brain. 7/. Horn-shaped process. 

 Te. Testis. Pe. Penis. GL Glands opening into ibe penis. Gl^ Glands 

 lying about the male aperture. ^. Male aperture. V.s. Vesicula seminalis. 

 Ov. Ovary. R. s. Receptaculum seminis. B. s. Bursa seminalis. Ch.a. 

 Ciiitinous appendage. Y.gl. Yolk gland. $. Female aperture. 



Fig. 2. — Various attitudes assumed in life. X about 10 times. 



Fig. 3. — Long. sec. through the pharynx. X 400. Ph.c. Pharynx cells. 

 O.L. Outer longitudinal muscles of [liiarynx. O.Cir. Outer circular muscles, 

 and I. L., inner longitudinal muscles of the same. Ph. E. Epithelium lining 

 llie lumen of the pharynx. Ph.T. Pharyngeal pouch. Ph. T^. Narrow [tart 

 of pharyngeal pouch. R.M. Radial muscles of pharynx. (The inner circular 

 muscles are seen as a row of dots immediately to the inside of the iniu-r 

 longitudinal fibres.) Sp. Sphincter muscle of the " mouth " aperture. A.M. 

 Muscles running from the anterior side of the pharynx to the body-wall. 

 Ex. M. Oilier extrinsic muscles of the pharynx. 



Fig. 4.— Trans, sec. through the pharynx region showing the gut diver- 

 ticulum {A. cL). I. c. Inner circular muscles of the pharynx. Oilier lettering 

 as in Fig. 4. 



Fig. 5.— Horizontal section through the pre-oral lobe. G. Ganglion cells. 

 Gl. Integumentary gland cells. Mo. Cells in morula stage in testis. N. 

 Nerve. Other lettering as in Fig. 1. 



Fig. 6 a. — Penial armature closed. 



Fig. 6 b. — The same evaginated, " much enlarged, drawn from life." Oh. 

 Chitinous tube. C. S. Chitinous spines. L, Lobes. 



Fig. 7. — Long. sec. through the penis and bursa seminalis (drawn from 

 two sections and combined). Oir. Circular muscle-fibres of body-wall. Lo?i. 

 Longitudinal fibres of body-wall. En. Endoderm. Ex. M. External muscular 

 capsule of the penis. J. M. Inner muscular layer of the same. M. 

 Muscle-fibres. Ar. Peninl armature. Sp. Sphincter muscle-fibres of female 

 aperture. B. s. Chamber into which the bursa seminalis opens. B. Sy 



