186 THE VOYAGE OF H.M.S. CHALLENGER. 



running five hours, and the S.W.-going stream seven hours. The alteration in the direc- 

 tion of the stream did not coincide with the times of high and low water at St. Vincent, 

 for the N.E. -going stream commenced three hours before high water, and the S.W.- 

 going stream two hours after high water. The maximum speed of the surface stream 

 was one mile per hour. The current drag at the bottom indicated an equality in the hours 

 of the stream there, as it ran six hours in each direction, the times of change being at half 

 flood or ebb ; it would, therefore, appear that the stream at the surface is affected by 

 the trade wind, the N.E.-going tide being retarded and the S.W.-going tide accelerated. 

 The maximum speed of the stream at the bottom was three-quarters of a mile per hour. 



In the harbour of St. Vincent the deposit in depths from 7 to 50 fathoms was a cal- 

 careous sand, with 87 to 94 per cent, of carbonate of lime, chiefly made up of Foraminifera 

 shells and calcareous Algae. In some places the shells of Amphistegina lessonii 

 made up fully two-thirds of the whole deposit. Polystomella, Discorbina, and Orbicu- 

 lina were also abundant. The deposits around the islands from 200 fathoms down to a 

 depth of 1150 fathoms were volcanic sands and muds, with from 13 to 50 per cent, of 

 carbonate of lime, in which Pteropod and Heteropod shells were abundant. 



Dr. v Willemoes Suhm writes as follows in his Journal :— " The following birds only 

 were observed near the settlement: — the Egyptian Vulture (Cathartes percnopterus) and 

 the common hooded crow, carrion crow and rook. The first of these, the sacred vulture 

 of the east, appears to breed in December and January, for at the time of our visit (July) 

 the young ones, recognisable by their brown plumage, were just beginning to moult. 

 Among the tamarisk trees was a small Platydactylus, and also a lizard. A small black 

 beetle was found under nearly every stone, and over a pool we observed two species 

 of dragon-fly, whilst an Acridium was jumping and flying over many of the stony 

 places. Where the tamarisk trees are high enough to afford shelter, insects are 

 in greatest abundance. An Ant-lion (Myrmeleon) of which we obtained both the larva 

 and imago, lies in wait for a small colonial species of ant. It somewhat resembles Agrion, 

 but can be distinguished from it by its slow flight and its habit of folding its wings when 

 sitting. Of Hymenoptera, 1 a large black Ichneumonid with yellow antennae, and another 

 wasp-like one may be mentioned. Diptera abound, especially the common meat-flies ; an 

 Osmcea was also noticed. Some fifteen or twenty species of Coleoptera were observed, 

 which, with few exceptions (Cicindela, Coccinella, very common among the tamarisks), 

 belong to the Melasomidse, a family characteristic of the shores of the Mediterranean and 

 the west coast of North and South America. There are some Silphidse, more of which 

 might perhaps be found beneath dead animals. Lepidoptera and Hemiptera seem to be 

 scarce ; one species only of the latter was found. A. Scolopendra, possibly brought by 

 ships, was not uncommon under stones ; a Geophilus may also be noted. We observed no 



1 Among the Hymenoptera collected were two new species, Priocnemis atlanticus, Kirby, and Polistes fortunatus, 

 Kirby, Ann. and Mag. Nat. Hist., ser. 5, vol. xiii. pp. 408^110, 1884. 



