32 bulletin: museum of comparative zoology. 



XIII. Fig. 2) is also apparently a remnant of the same level as the John 

 Crow Bench, but the writer cannot positively establish this fact as he 

 did not ascend to the summit of this hill. Probably Dolphin Head 

 (alt. 1,800 feet) and other points of Hanover near the west end of the 

 island are remnants of the John Crow level. 



The next persistent level traceable in the back coast topography 

 closely corresponds with the altitude of 1,500 feet. This is etched with 

 great clearness upon the outline of the island, being noticeable as the 

 long horizontal sky line of many of the so called mountains of which 

 Long Mountain east of Kingston is a conspicuous type. On the south 

 side of the island this is widely developed at many places, notably at 

 Cambridge Hill (alt. 1,521 feet) west of the Yallahs River; Mount 

 Salas (alt. 1,561 feet) ; Long Mountain, near Kingston (alt. 1,490 feet) ; 

 and several localities along the coast of St. Elizabeth and Manchester, 

 and the coast of Westmoreland at Hopeton. Another notable extent 

 of this level is seen to the right of Porus along the railway towards 

 Montego Bay. This general level is not visible in the north coast 

 topography. 



The next conspicuous bench has an altitude closely approximating 

 1,000 feet, the known altitudes ranging from 9G1 to 1,035 feet. This 

 level is that of a greatly dissected plain, which dominates the summit 

 topography of the back coast country of the north side of the island 

 west of Port Antonio, and out of which all the lower terraces shown in 

 the picture of Montego Bay (Plate XX.) have been cut. These summits 

 called the '' North Coast Ranges " are especially characteristic of a wide 

 strip of country in Hanover, St. James, Trelawney, St. Ann, and St. 

 Mary. On the south coast it is well marked, constituting the angular 

 bench of the Yallahs Mountain profile, and a conspicuous ridge to the 

 east towards Morant Bay as shown in Plate XIII. Fig. 2. These 

 benches at the 2,100, 1,500, and 1,000 foot levels, are connected 

 phenomena and represent a distinct stage of elevation in Antillean 

 history. 



FiouRB 9. Profile, East Side of Montego Bay, showing Benches. 



A lower group of bench levels occurs at altitudes of 650, 300, and 

 200 feet, becoming more distinct and persistent with decreasing alti- 

 tude. The terraces of the Montego profile shown in Figure 9 mostly 



