174 D. d' EMMEREZ DE CHARMOY. 



Lecanium mangiferae. 



The importation of this scale probably does not date back further than 1907, 

 as it was only in 1908 that the first infested trees were recorded in Moka. It would 

 be difficult to state its origin, as the author has observed it in Madagascar and in 

 Reunion in 1917, where many trees, especially mangoes, were severely attacked. 

 In this Colony, it is in Grand Port and especially in the town of Mahebourg that 

 this insect causes most damage. Mangoes, bread-fruits, Cinnamomum zeylanicum 

 (cannelher) and litchis are often infested to such a degree that they do not bear 

 fruit for several years. In the north of the island, where it exists, its presence 

 is not apparent, either on account of unfavourable cUmatic conditions, or owing 

 to a small Chalcid which parasitises it intensely. 



Lecanium hesperidum. 



It seems curious that this species, the distribution of which is world-wide, should 

 not have been found in Mauritius before 1900. The effects of the insect are so 

 striking that it is inadmissible that it could have escaped the author's notice at the 

 time when this group of insects was being worked upon. It was introduced from 

 the Seychelles or from Madagascar with oranges. On the higher plateaux its 

 presence is hardly perceptible, but it is much in evidence along the coast, where 

 Hmes, particularly, suffer severely from its attacks. 



Pulvinaria antigoni. 



This species was introduced some 10 years ago from the Seychelles ; it was first 

 discovered in Pamplemousses Gardens and a Httle later at Phoenix on Solanum 

 wildenii and on Aristolochia. It is far from being widespread in the island and is 

 relatively common on these plants for only a few months of the year, being highly 

 parasitised by two minute Chalcids. It is up to now of no economic importance. 



Gagrella feae. 



This Phalangid, which was imported from Burma some 10 years ago with cargos 

 of rice from Rangoon, is a striking instance of the rapidity with which an exotic 

 insect can spread itself, when conditions prove favourable to its development and 

 when nothing intervenes to check its spread and multiphcation. The first specimens 

 were seen by the author in 1910 and had been captured in the town of Port Louis by 

 Mr. Lauricourt Ohvia, taxidermist to the Museum. Three years later it had reached 

 Grand River, i.e., 26 miles from the original point of occurrence, and in the course 

 of the five following years, the other districts of the Island had all become more 

 or less invaded ; nowadays it is to be found everywhere. It has estabhshed itself 

 in all towns and has crept over to the forests, where it exists in considerable numbers. 

 It is sometimes so common in houses as to constitute a regular domestic pest. 



These Phalangids shun light and have the habit of collecting in considerable 

 numbers in dark places. They spread out rapidly whenever they are disturbed, 

 but will come back soon afterwards. 



