862 DR RAMSAY II. TRAQUAIR ON FOSSIL FISHES COLLECTED BY THE 



40. "Woodward, A. Smith. — " Edward Drinker Cope" (obituary notice). Natural. Science, vol. x., 1897, 

 PI'. 377-381. 



41. Woodward, A. Smith. — "Outlines of Vertebrate Palaeontology." Cambridge, 1898. 



42. Zittel, C. v. — "Handbuck der Palreontologie." Division I., vol. iii. pt.'l. Munich and Leipzig, 1887. 



43. Zittel, C. v. — "Grundzuge der Palrcontologie (Palreozoologie)." Munich and Leipzig, 1895. 



EXPLANATION OF THE PLATES. 



Plate I. 

 Thelodus Scoticus, Traq. 



Fig. 1. A specimen from the " Ceratiocaris Band," Logan Water. Natural size. The head is imper- 

 fect, but the sculpture and arrangement of the scales is exceedingly well shown in places. 



Fig. 2. Another specimen from the same horizon and locality. Natural size. The contour in front is 

 somewhat obscured by distortion. 



Fig. 3. A specimen from the Downtonian horizon at Seggholm, showing the shape of the body 

 unusually well. Natural size. 



Fig. 4. Another specimen from a similar horizon at Monk's Burn. 



Fig. 5. Upper surface of an isolated head-scale from Logan Water, magnified twenty diameters. 



Fig. 6. The same scale, from below. 



Fig. 7. The same scale, from the side. 



Fig. 8. Upper surface of a scale from behind the head, also from Logan Water, magnified twenty 

 diameters. 



Fig. 9. A similar scale seen from the side, magnified twenty diameters. 



Fig. 10. Arrangement of the posterior scales, from the specimen represented in fig. 1. Same 

 enlargement as in figs. 8 and 9. 



Plate II. 



Thelodus planus, Traq. 



Fig. 1. Entire specimen, natural size, from the " Ceratiocaris Band," Logan Water. 

 Fig. 2. Scales from the front ; outer surface, magnified eight diameters. 

 Fig. 3. Scales from the caudal region, outer surface ; same enlargement. 



Plate III. 



Lanarkia horrida, Traq. 



Fig. 1. Specimen, showing the head region well, but imperfect posteriorly. Downtonian, Birkenhead 

 Burn. Enlarged by one half. 



Fig. 2. Another specimen from the same horizon and locality, showing a nearly perfect caudal 

 extremity. Also enlarged one half. 



Figs. 3-4. Isolated dermal spines, magnified twelve diameters. 



Fig. 5. Natural cast of the interior of a spine, seen from above, apex broken off ; same enlargement. 



Fig. 6. A group of similar spines ; same enlargement. . 





