A REMARKABLE NEW ISLAND ISOLATE 
IN THE ANT GENUS PR 0 CERAT 1 UM 
(HYMENOPTERA: FORMICIDAE) 
By William L. Brown, Jr.* 
Department of Entomology 
Cornell University 
Ithaca, New York 14850 
In 1969, I collected in southern Africa and Madagascar, and then 
moved on for work in southern India, stopping en route for four 
days (29 March- 1 April) on Mauritius in order to sample the small 
but interesting endemic ant fauna known from this island in the 
Indian Ocean. My experience there was greatly enriched by aid and 
information from Mr. Leo Edgerly, retired chief forester of Mauri- 
tius, whose knowledge of the island and its plants, animals and people 
is probably unmatched. 
On the second day of my stay, on Mr. Edgerly’s advice, I climbed 
the small mountain known as Le Pouce (“The Thumb”) in the 
Moka Range in the northern part of the island. This mountain, 
formerly collected by the Mauritian entomologists R. Mamet and 
J. Vinson, is described in Donisthorpe’s paper (1946) on the ants 
of Mauritius. The Moka Range rises from a sea of sugar cane, and 
Le Pouce is separated from neighboring mountains in the narrow 
volcanic chain by deep saddles. It is an elongate massif, with tall, 
steeply dropping cliffs on all sides and a topside “plateau” sloping up 
gently eastward to a sudden sharp peak that gives the mountain its 
name. The plateau averages about 700 m in elevation; it is still 
largely covered with a low, gnarled native forest much invaded by 
guava and grassland. A mostly gentle trail hugs the cliffs and crosses 
the plateau. 
The first day on Le Pouce was a bright, sunny Sunday, and the 
few well-marked trails through the pleateau scrub were invaded by 
bands of teenagers from the lowlands, equipped with portable radios. 
Accordingly, I stuck to the heavy vegetation. Ants were very scarce, 
and nearly all that I found were colonies of the small dark Solenop- 
*This work was supported by United States National Science Foundation 
Grant GB-31662 and an earlier grant from the same agency; the support is 
gratefully acknowledged. 
Manuscript received by the editor February 15, 1974 
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