334 WILLIAM A. HASWELL. 



EXPLANATION OF PLATES 14 and 15, 



Illustrating' Prof. William A. Haswell's papei- '^On a New 

 Histriobdellid." 



List of Reference Lellers. 



cic. Accessory glands of iDale reproductive apparatus, br. Bridle pieces of 

 jaws. br. c. Nerve-cells of brain, hr.f. fibrous matter of brain, c. Cirrus. 

 cl. Clasper. en. CEsopliageal connective, coe,. Cceloni. cce. ep. Coelomic 

 epithelium. /. Fulcrum of upper jaw. fol. FoUiclfi of large ovum. gl. cl. 

 Gland of clasper. gii. cd. Ganglion of nerve-cord. g)i. t. Tentacular 

 ganglion, gr. gld. Granule glands, int. Intestine, j} Upper jaw. j.^ 

 Lower jaw. /. a. Anterior legs. I. al. Leg gland. /. p. Posterior leg. 

 m. Mouth, m. d. Dorsal longitudinal muscles, m. ob. Oblique muscles. 

 m. V. Ventral longitudinal muscles, neph. Nephridium. n. I. Lateral nerve. 

 od. Oviduct, oes. ffisophagus. ov. Ovary, f. Penis, p.j. Muscular fibres 

 supposed to act as protractors of jaws. pro. m. Protractor muscles of penis. 

 r. Ramus of upper jaw. r. cl. Retractors of clasper. reir. m. Retractor 

 muscles of penis, r. j. Retractor muscles of jaws. r. I. a. Retractors of 

 anterior legs. st. Stomach, str. m. Striated muscle of jaws, t.^ Median 

 tentacle, t.^ t.^ Lateral tentacles, te. Testis, v. def. Vas deferens, vei. 

 Vesicula seminalis. vit. Vitellarium. 



Fig. 1. — Entire male of Stratiodrilus tasmanicus. X 200. The 

 outline drawn from a living specimen with the aid of camera lucida : nervous 

 system coloured blue, muscles red, nephridia (including vasa deferentia) 

 green. To avoid too great complication the ganglion situated on the dorsal 

 side of the penis and the oesophageal connectives have been omitted. 



Fig. 2. — Outline of female specimen with the nervous system (coloured 

 blue). 



Fig. 3. — Transverse section of a portion of one of the longitudinal bands 

 of muscular fibres, the coelomic surface below, x 1500. 



Fig. 4. — Jaws with the rami retracted, ventral view. X 800. 



Fig. 5.— Jaws with the rami everted, ventral view. 



Fig. 6. — Approximately transverse section of head in the brain region. 



Fig. 7. — Transverse section of head behind the brain region in the region 

 of the anterior legs. 



Fig. 8. — Longitudinal vertical section of head, approximately median. 



Fig. 9. — Transverse section of the second segment, immediately behind 

 the first pair of cirri. 



