352 EXPLANATION OF THE PLATES. 



Plate III. 



Various kinds of bristles connected with the feet, <fec., of Annelides 

 (simple bristles), figs. 1-23 : — magnified. 



Fig. 1. A spine (aciculus) ; generally one or two occur in each fascicle 

 of bristles in each foot. 2. A forcipate spinet. 3, 3*-5. 

 Forked spinets. 6, 7. Setaceous bristles. 8, 9. Yentricose 

 bristles. 10,11,13,14. Lanceolate bristles. 15. ? A seta be- 

 longing to Lepidonotus pellucidus. 17-19. Tarsiform bristles 

 from the superior and inferior branches of one of the feet of 

 Lepidonotua pilar etratus. 21-23. Spinous bristles. 



Plate IV. 



Various kinds of bristles connected 'with the feet, &c., of Anne- 

 lides : — magnified. 



Figs. 1-13. Compound bristles, peculiar to the Annelida rapacea. 

 The compound bristles are bristles of which the shaft is broken 

 into two halves by an imperfect sort of joint ; the lower portion 

 is the shaft, and the upper the terminal piece. Fig. 1 is a 

 tarsiform compound bristle. Figs. 2, 6 &; 12 are falcate com- 

 pound bristles. Fig. 7 is an acicular compound bristle. Figs. 

 5 & 6. Two bristles of the ventral branch of Lepidonotus clava. 

 Figs. 14-17 are booklets of one of the feet (uncini) ; almost pecu- 

 liar to the tubicolous Annelides, the Terebellidae, Serpulidae, &c. 



Plate V, 

 Lepidonotus semisculptus. 



Fig. 1. The animal magnified : the line by its side shows the natural 

 size*. 2. The head magnified, under surface. 3. Spine? 7-11. 

 Various bristles, magnified. 



Plate VI. 



Fig. 4 of Plate V. A scale of Lepidonotus semisculptus. Fig. 5 of 

 Plate V. Section of a segment of the body of ditto. Fig. 6 of 

 Plate V. One of the feet of ditto : — aU magnified. 



Figs. 1-5. PJioloe eximia. 1. Animal magnified. 2. A scale; one of 

 the upper twelve. 3. One of the ventral bristles. 4. One of 

 the jaws. 5. One of the dorsal bristles : — all magnified. 



* Unfortunately, the specimen mentioned by Dr. Johnston is not in the Col- 

 lection, and though the figure agrees in most respects with his description, it 

 does not tally with it in the number of scales. He describes the animal as pos- 

 sessing 15 pairs, the figure represents 20. A specimen of a Lepidonotus lately 

 received from Guernsey, and now in the Museum Collection, and which I con- 

 sider as being L. semisculptus, has 20 pairs of scales, and therefore, perhaps, the 

 number 15 may be a misprint not corrected by Dr. Johnston as the MS. went 

 through the press. — W. B. 



