JOURNAL OF MICROSCOPICAL SCIENCE. 



EXPLANATION OF PLATES VI, VII, VIII, IX, X, 

 XI, & XII, 



Illustrating Professor Lankester^s Memoir on the " Skeleto- 

 trophic Tissues and Coxal Glands of Limulus, Scorpio, 

 and Mygale." 



PLATE VI. 



Fig. 1. — Entosternite or prosomatic plastron of Limulus, dorsal surface. 

 Ph. N. Pharyngeal notch, where the pharynx is embraced by the entosternite. 

 L. A. P. Left anterior process or cornu. B. A. P. Right anterior cornu. 

 A. L. B. Anterior lateral rod or tendon (paired). P. L. B. Posterior lateral 

 rod or tendon (paired). P. L. P. Posterior lateral process or cornu (paired). 

 The bifurcate median posterior process is not lettered. Natural size. 



Fig. 2.- — View of ventral surface of the same. N. F. Neural fossa, in 

 which the great prosomatic ganglia lie. P. M. P. Posterior median process. 

 P. V. P. Posterior ventral process. Other letters as in Fig. 1. Natural size. 



Fig. 3. — Ventral view of the entosternite of Mygale sp. PL N. Pharyn- 

 geal notch. Magnified seven diameters. 



Fig. 4. — Dorsal view of the entosternite of Mygale. Pk. N. Pharyngeal 

 notch. The three pairs of upstanding rod-like processes correspond to the 

 two pairs of lateral rod-like processes, A. L. B., P. L. B., of Limulus. 

 Observe also the close similarity of the posterior median process in Mygale 

 and Limulus. Magnified seven diameters. 



Fig. 5. — Dorsal view of the entosternite of a scorpion (Buthus cyaneus 

 of Ceylon), a. p. Anterior process (paired). /. m.p. Lateral median pro- 

 cess (paired), pp. Posterior lateral process (paired), p./. Posterior flap, a 

 wide-spreading diaphragm-like outgrowth from the posterior lateral processes. 

 G. C. Gastric canal. A. C. Arterial canal. D. B. Dorsal ridge (paired). 

 Snp. subneural arch. asp. Anterior process (paired) of the subneural arch. 

 m^. Anterior muscular perforation (paired) of the posterior flap. nP. Posterior 

 muscular perforation (paired) of the posterior flap. Magnified ten diameters. 



Fig. 6. — Ventral view of the entosternite of a scorpion (Buthus cyaneus 

 of Ceylon). B. A. P. Right anterior process. Z. A. P. Left anterior pro- 

 cess. I. m.p. Lateral median process (paired), p.p. Posterior process 

 (paired), p.f. Posterior flap. Snp. Subneural arch. asp. Anterior process 



