138 BULLETIN OF THE MUSEUM OF COMPAEATIVE ZOOLOGY. 



PLATE IV. 



Fig. 12. Overlying sandstone traversed by a small leader from the trap sheet of 

 Gay lord's Mountain at lioaring Brook, locality 3. See pp. 115 and 

 116. 



Fig. 13. Angular fragments of trap imbedded in sandstone on the back of the 

 anterior ridge of Higby Mountain, half a mile southeast of East Meri- 

 den, locality 5. See p. 107. 



Fig. 14. Drawing from a microphotograph of a section of vesicular trap from the 

 ridge posterior to Chauncy Peak at Highland Lake, locality 24. Tlie 

 trap is black, with white areas representing minute pseud-amygdules 

 and an occasional prism of plagioclase ; the large central space within 

 the trap is an amygdule, containing clastic material (dotted) at the 

 bottom, with the once horizontal lines of deposition now tilted parallel 

 to the general monocline of the region ; the upper part of the amyg- 

 dule is filled with calcite, of which part is stained with some ferrugi- 

 nous material (fine lines), and the rest is composite crystalline calcite 

 (blank). See p. 115. 



Fig. 15. Drawing from photograph of sandstone in contact with vesicular upper 

 surface of trap, forming Lamentation Mountain, locality 18. The 

 black areas are the thin walls separating vesicles ; white spaces are 

 amygdules of calcite. See p. 112. 



Fig. 16. Drawing from photograph of hand specimen of sand grains filling open 

 vesicles in trap. Falls of the Aramamit Kiver. Two vesicles have 

 lower bands of calcite, and the remaining space filled with clastic 

 material. Locality 23, see p. 114. 



Fig. 17. Breccia from fault in a road-cut in the second posterior ridge to Salton- 

 stall Mountain, near Branford, locality 21. This fault is probably a 

 branch of the great fault by which the Triassic formation is limited on 

 the east. See p. 114. 



PLATE V. 



Fig. 18. The City Quarry at Meriden, looking northwest ; locality 19. a, a, 

 the -lower tiow in the southern part and the western alcove of the 

 quarry ; b, b, b, the upper flow, forming most of the mass here exposed ; 

 c, c, c, breccias of angular trap fragments and sandstone, traversing 

 the quarry. See pp. 112, 127. The northern extension of Cat-hole 

 Ridge is seen in the distance. 



