Occasional Papers of the Museum of Zoology 23 



of the canyon-like roois around Savaneta (I), are also pre- 

 cipitous. The southwestern side of the island is protected by 

 a series of coral reefs, which often form narrow islands, less 

 than a kilometer off shore (fig. v-12). 



In the diabasic portion of the central region,^" Seroe 

 Jamanota (J), the highest hill (188.37 meters) on the island, 

 is considerably lower and much less wooded than are the 

 higher hills in Curagao and Bonaire. The northern half of 

 Aruba has a core of quartz-diorite, which closely resembles the 

 rocks of the Pikes Peak Region in Colorado, and also contains 

 veins of gold. Enormous, rounded boulders of this material, 

 which are often hollowed out on their leeward sides, and out- 

 wash fans of angular gravel are conspicuous features of the 

 landscape in this portion.-^ 



Although the molluscan fauna changes slightly at Spaansch 

 Lagoen (M), Aruba is more nearly a unit than is the case 

 with Curasao. 



Station Al. Culehra (A; L69° 52.99', 12° 25.26'). Near 

 the southern end of Aruba is a rolling plain of the older lime- 

 stone, with many sink-holes, which contain the characteristic 

 reddish residuum. Most of the shells were collected around 

 the buildings of an abandoned mining camp, near the phos- 

 phate deposits. Subfossil Cerion uva is common in this local- 

 ity, but no living specimens could be found. The eastern shore 

 near Boca Grandi (C) is built up with sand dunes, partially 

 held by clumps of ''dreifi" trees (Coccoloha uvifera). Most 

 of the region is very barren and resembles CIO. 



Station A2. This includes the higher plateaus and mesas of 

 the ancient limestone, south of Spaansch Lagoen. Most of the 

 specimens collected came from three localities. 



A2a. Near Butucoe (D; L69° 55.44', 12° 28.23'). ^^ This 

 lot comes from a small, wooded valley near the southern edge 

 of Baranca Kasiocnti. The higher portions of this plateau are 

 about as heavily wooded as any portion of the limestone areas 

 in the islands. 



20 See Boldingh, p. 160; "Mirlamar." 



21 See K. Martin, II, p. 47, fig. 15. 



22 See Boldingh, p. 159, "The calcareous table-land near Fontein. " 



