98 
tained by the two expeditions is about 90. The total land flora 
of Desecheo is thus, presumably, not over 200 species; all but 
four or five are there naturally, there having been no cultivation 
on this island, which is ordinarliy visited only by fishermen. 
Desecheo is a national bird preserve, and several kinds of 
water-birds nest there in large numbers. We had to pick our 
way over much of the island to avoid stepping on eggs. The 
only available landing place under ordinary conditions of wind 
and sea is on the southwestern side, a small harbor with rock 
sides and a gravel beach, where we landed from the small boat 
of the sloop, and where we were trapped for a day and a night, 
the heavy seas preventing a return to the vessel. Luckily, we 
had plenty of water and our gunny-sacks filled with hay, o 
which we slept under overhanging ledges, after becoming ac- 
customed to the loud music of the breakers on the little beach. 
Most of the flowering plants of Desecheo are found also on the 
southern, dry side of the Porto Rican mainland, but the snowy 
cactus (Mamillaria nivosa) and Morisonia americana, a small 
tree of the Caper Family, have not yet been found there, pana 
both occur on Culebra Island, just east of Porto 
rainfall of Desecheo and its steep configuration mare it una- 
vailable for pene work. It might come into use for 
forestation, but it is probably more valuable as a bird preserve 
than any other a. The island is not inhabited. 
At 8 o’clock in the morning, February 20, we set sail for Mona 
Island, about 30 miles to the sou thwest, and lying almost exactly 
midway between Porto Rico and Santo Domingo, casting anchor 
at Sardifiera at 5 in the afternoon. Through the kind permission 
of the Mona Island Fertilizer Company, we made camp in one 
of their buildings at this point; to Mr. Marc Lejeune, manager 
of this company at Mayaguez, we are grateful for aid and advice. 
Mona has an area of perhaps 20 square miles; most of it is a 
limestone plateau, elevated at its highest point about 175 feet 
above the ocean, and nearly level, there being no hills; the surface 
of this plateau is rough and rocky, with scarcely any soil, aia 
densely clothed with shrubs and small trees of a numbe 
species; what soil there is occupies small pockets in the uneven 
