I \\.\l ION ,,i i 4653. liii 



EXPLANATION OF II -53'. (XXV. p. 871.) 



COMPLETE LIST OF REFERENCE LETTERS. 



A. .\iiu~. a. Dorso-latcral horn <>f white matter in l.r.iin. a.g. Accessory gland 

 of male (modified accessory le^ gland), at. Antenna. ,//. ;/. Antennary nerve, b. 

 Ventro-lateral horn of white matter of brain. b. c. Body-cavity. bl. Hlastopore. 

 C. Cutis. c. Postero-dorsal lobe of white matter of brain. e.g. Supracesophageal 

 i;ani;lia. d. Claw. c. m. Circular layer of muscles, co. Commissures between the 

 ventral nerve-cords, co.i. Second commi^u; the ventral nerve-cords. 



co l .i. Mass of cells developed on second comminute, cor. Cornea, c. $.d. Com- 

 mon duct for the two salivary glan Ventral protuberance of 

 brain. d.l.m. Dorsal longitudinal muscle of pharynx. d.n. Median dorsal nerve 

 to integument from supraoesophageal ganglia, if. o. Muscular bands passing from the 

 ventro-lateral wall of the pharynx at the region of its opening into the buccal cavity, 

 i . Eye. E. Central lobe of white matter of brain, e. n. Nerves passing outwards from 

 the ventral cords, ep. Epidermis, tp. c. Epidermis cells. F. r , F. 2, &>t. First and 

 second pair of feet, &c. /. Small accessory glandular tubes of the male generative 

 apparatus, f.g. Ganglionic enlargement on ventral nerve-cord, from which a pair of 

 nerves to foot pass off. /. gl. Accessory foot-gland. F. n. Nerves to feet. g. co. 

 Commissures between the ventral nerve-cords containing ganglion cells, g. o. Gene- 

 rative orifice. H. Heart, h. Cells in lateral division of body-cavity. hy. Hypo- 

 blast, i.j. Inner jaw. j. Jaw. / n. Nerves to jaws. L. Lips. /. Lens. /. b. c. 

 Lateral compartment of body-cavity. U. Jaw lever (cuticular prolongation of inner 

 jaw lying in a backward ly projecting diverticulum of the buccal cavity). /. m. Bands 

 of longitudinal muscles. M. Buccal cavity. M 1 . Median backward diverticulum of 

 mouth or common salivary duct which receives the salivary ducts, nu. Mesenteron. 

 nics. Mesoblastic somite. ///./. Muscles of jaw lever, m. s. Sheets of muscle passing 

 round the side walls of pharynx to dorsal body wall. od. Oviduct, at. (Esophagus. 

 as. co. CEsophageal commissures, o.f. g. Orifice of duct of foot-gland, o.j. Outer 

 jaw. op. Optic ganglion, op. n. Optic nerve, or.g. Ganglionic enlargements for 

 oral papillae, or. n. Nerves to oral papillae, or. p. Oral papilla-, o. s. Orifice of 

 duct of segmental organ, ov. Ovary. P. Pads on ventral side of foot. /. Common 

 duct into which the vasa deferentia open. /. c. Posterior lobe of brain, p. d. c. 

 Posterior commissure passing dorsal to rectum. /./. Internal opening of nephridium 

 into body cavity. ///. Pharynx. //. Pigment in outer ends of epidermic cells. 

 Retinal pigment, p.n. Nerves to feet. /./. Primary papilla, pr. Prostate. R. 

 Rectum. Rt. Retinal rods. R. ///. Muscle of claw. s. Vesicle of nephridium. s 1 . 

 Part of 4th or 5th nephridium which corresponds to vesicle of other nephridia. 

 s. c. [. Region No. i of coiled tube of nephridium. s.c.i. Region No. i of ditto. 

 s. c. 3. Region No. 3 of ditto, s. c. 4. Region No. 4 of ditto, s. d. Salivary duct. 

 s. g. Salivary gland, sl.d. Reservoir of slime gland, st.g. Tubules of slime gland. 

 s. o. i, 2, 3, 6-v. Nephridia of ist, and, &c., feet. s. o.f. Terminal portion of nephri- 

 dium. s.p. Secondary papilla, st. Stomach, st. <. Epithelium of stomach, jry. 

 Sympathetic nerve running in muscles of tongue and pharynx, jry 1 . Origin of pharyn- 



1 The explanations of the figures printed within inv 

 the rest are by the Editors. 



