236 bulletin: museum of comparative zoology. 



Wallace lays great stress upon the pumice thrown up from the sea as 

 being a possible explanation of the source of red earth. Although I 

 examined the beaches of the south shore many times, I never succeeded 

 in finding a single piece of pumice. Tied earth is abundant, both at the 

 Bahamas and Bermudas, in localities to which drift pumice could not 

 have access. 



I was greatly struck with the apparent want of adaptation to their 

 surroundings of the coloring of many of the Bermudian marine inverte- 

 brates. The dark violet Diadema and Echinometra are very common on 

 the faces of the steep rocky patches, as well as in the sandy hollows of 

 the surface of the bank. In the one case they are part of the brilliant 

 patchwork forming the coloring of the reef surface; in the other, they 

 stand out most prominently against the whitish Nullipores. Diadema 

 in Florida, as well as in the Bahamas, is often found in colonies entirely 

 filling the bottom of some sandy depression in the midst of a white 

 field of surrounding coralline bottom, the patches of brilliantly col- 

 ored corals and Gorgonians themselves standing out as a whole in 

 striking contrast to the whitish bands of coralline or geolian sand sep- 

 arating them. 



Professor Heilprin has greatly added to our knowledge of the fauna of 

 the islands, 1 which was previously mainly derived from the sketch of their 

 Natural History by Jones, 2 and has also given a list of the species of 

 corals belonging to the islands. 8 



The low tides prevailing during the last days of my stay at the Ber- 

 mudas enabled me to note the luxuriant growth of Millepores and Gor- 

 gonians on the surface of the many patches which were nearly awash 

 during these days. The flats extending to the north of Ireland Island, 

 and the flats to the southeast of the North Rock Ledge, were specially 

 noteworthy for their abundant coral growths. 



On passing through Mangrove Bay to reach Hogfish Cut from Great 

 Sound, we dredged Oculinse from the deepest part of the bay ; the bottom 

 in four fathoms is very fine sticky silt, almost marl. Corals in Hamil- 

 ton Harbor, Great Sound, and Port Royal Bay are limited to a very 

 scattered growth along the shores of the islands of these sounds below 

 low-water mark. In the deeper parts of the sounds Oculinse grow to 

 considerable size. Zoanthidaa are abundant on the higher knolls of the 

 outer reef, and also on the serpnline atoll-like structures. Porites is 

 quite common on the outer reef. This is in marked contrast to the 



1 Bermudas, p. 07. 3 Bermudas, p. 98. 



2 The Naturalist in the Rermudas. 



