INTRODUCTION — WAITE. 15 



familiiif s;iii(.l hoppers, Ts()i)ods, marine representatives of the 

 jtjarden woodlouse, and Cope^jods, all eagerly devoured by fishes. 

 Of the shell-fish kind we observe lanthinn, Giauciif<, and the 

 Pteropods and Heteropods, in which the body is transpai-ent and 

 the shell almost obsolete. Numerous small MudtiHa, or jelly fishes, 

 are also washed up, and if these are not actually (;aten the}"^ form 

 food for other creatures preyed upon by fishes. The FliyticUia, better 

 known as the Portuguese Man-o-'war, is a familiar and abundant 

 animal, dreaded for its stinging properties. Mr. T. Whitelegge 

 tells me that he has often seen small fish in their stomachs 

 and entangled in their tentacles. Velella is an allied animal 

 frequently associated with Physalia. These are some of the 

 principal pelagic types met with, but hosts of other forms also 

 occur ; some of these are quite erratic in their appearance. At 

 times the waters off shore and in the harbour become greatly 

 discoloured, and in places even present the appearance of blood. 

 Mr. Whitelegge, who investigated this matter,* found that it is 

 due to the presence of a small organism, Glenodiaiiiin rubi'um, 

 which swarms to such an extent as to discolour the water for 

 miles and miles. 



Organisms belonging to the same group are largely preyed upon 

 by fishes, and there is little doubt that our Glenodinium is to be 

 ranked as a bountiful supply directly or indirectly. MM. Pouchet 

 and Guerne, who examined some sardines, found their viscera 

 literally filled with species of Peridinia, and estimated that the 

 digestive tract of a single fish contained no less than twenty 

 million individuals, f 



It is, however, difficult to give any idea of the wealth of minute 

 life at the surface of the ocean ; it is sometimes washed ashore in 

 such profusion that the rocks become dangerously slippery with a 

 thick deposit, whilst the water in the rock pools is thickened by 

 the abundance of Saljm and other forms. Associated with them 

 are crowds of Copej)ods. Every object in the water is peopled 

 with them ; shake a piece of seaweed in a bottle and thousands 

 are disturbed ; when dead they settle as a thick sediment. 



It must be remembered that I am not writing of food in the 

 sea generally, but only of that found at the surface. This surface 

 life is much influenced by the weather ; if a shower disturbs the 

 surface the minute organisms sink, and then cease to be washed 

 ashore. The sudden disappearance of a shoal of fish might be 

 thus accounted for. 



* Whitelegge— Rec. Ai;st. Mus., i., 1891, pp. 144 and 179. 

 t Pouchet and Guerne — Comptes Rendus, 1887, p. 712. 



