286 YACHT EQUIPMENT 



numbers of indeterminable forms will be found ; these 

 may be entered as Gadoid A, Asteroid A, etc. The 

 same species occurring in subsequent hauls should be 

 referred to in the same way, but unless the identity 

 of the two forms is certain a sample must again be 

 preserved. 



When possible the stomachs of fish should be ex- 

 amined, for, apart from the light which is thus thrown 

 on the food-supply of the species, they occasionally 

 contain invertebrates which are seldom or never found 

 in any other way. 



Search should be made for hermit crabs and worms 

 resident in the dead shells of molluscs, and for en- 

 crusting animals living on stones or other debris. As a 

 rule it is best to avoid attempts at extraction or removal. 



The comparatively large animals, obtained in bags 

 of sprat meshing, may be dealt with in the same way, 

 but the sorting of the material collected by the fine- 

 meshed nets usually demands so much time that im- 

 mediate treatment is out of the question. In such cases 

 it is best to transfer the whole to a jar containing 5 per 

 cent, formalin or formol-alcohol, until a more favour- 

 able occasion arises. It should be remembered that 

 formalin, even in a 5 per cent, solution, is sufficiently 

 acid to act as a decalcifying agent ; all animals which 

 are liable to injury from this cause should be trans- 

 ferred as soon as possible to 70 or 75 per cent, alcohol. 



The sand, mud, or ooze, which is sometimes brought 

 up in considerable quantity by the trawl or dredge, 

 generally contains a considerable number of animals. 

 For the treatment of this material sieves must be 

 employed ; the process is rather laborious, but the 

 results are as a rule eminently satisfactory. It is 

 best to obtain a set of four sieves (with different sized 

 meshes), which may be employed successively, using the 



