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used for shading the cocoa seem to be preferred by insects, 

 ■worms and snails on account of their soft Avood. 



There is much to be done in Trinidad, in the sweet water 

 fauna, as this subject, is nearly untouched. I shall now make 

 a few remarks on it, keeping the different forms of water dis- 

 tinct according to their character, as these have much influence , 

 on their inhabitants. There are four forms of water in Trini- 

 dad, which with the exception of some widely distributed 

 species have their special fauna viz : 1. The mountain rivulets. 

 2. The canals with slow-flowing water, principally on sugar 

 estates 3, Ponds. 4. The larger rivers as Caroni, Ortoire etc. 

 1. The mountain rivulets take their origin high up the 

 northern chain of hills and there are a good many of them. 

 Their Avater is clear and comparatively cold and their course 

 is rapid, forming little cataracts in many places. Most of them 

 flow to the South and fall into the Caroui. Thej' are inhabited 

 by few species of animals ; there are several species of small 

 fish, some cray fish, belonging to the gems Atya, which live 

 under stones and under the plants growing on the banks, insect 

 larvfe and few worms; I have never seen snails in them. Most 

 of the animals living in these rivulets protect themselves 

 against the strong current either, that they choose the washed 

 out holes in the beds of the stream (as the fish and cray fish) or 

 they keep themselves behind and under stones, or that they 

 have special organs of suction with which they attach themselves 

 to the stones. A Plccostomus species (Mamam Cascaladou) 

 especially does this, and it sticks on so firmly to the stones that 

 it can hardly be detached without injury, ^ome insect larvag have 

 suction valves on their ventral surface, with which the\ stick on 

 to the stones over-grown with algcc on which they feed. The 

 worms are represented by some Clepsines and few Planaria, 

 I would like to call attention here to a small fish, that occurs in 

 every form of water without exception. It is a small Cyprin 

 odonte about 5 cm. long, generally smaller. The males are very 

 pretty during the breeding season ; on the brown green ground 



