ON COLLECTING AND PRESERVING FISHES 75 
ON COLLECTING AND PRESERVING FISHES 
By G. A. Boulenger 
It is often believed that the fishes of British East Africa 
are comparatively well known, and considering the trouble 
incurred in preserving and transporting specimens in spirit, 
many travellers neglect this group of Zoology and turn their 
attention to others more likely, in their opinion, to yield 
interesting results. Nothing, however, could be more erroneous, 
as among the collections that have been made in East Africa 
within the last decade, fishes have invariably proved of great 
interest. There is no doubt that they are more imperfectly 
known than reptiles or batrachians. 
It has been my privilege to describe something like seventy 
new species of fishes from within the limits of British East 
Africa, yet, a few months ago, quite a small collection made 
by Mr. Blayney Percival has added two to the list. It is 
especially among such small Silurids (cat-fish) and Cyprinids 
(barbels and other carp-like fishes) that live in mountain 
streams that important discoveries are likely to be made. 
Difficulties of preservation and transport constitute the 
usual objection to making such collections, but if travellers 
would bear in mind that even small specimens, from one to six 
inches in length, which may be easily preserved in small jars 
or corked tubes, are likely to prove valuable, knowledge would 
be rapidly increased. 
Spirit, pure or methylated alcohol if possible, is the only 
preserving fluid to be recommended. Collectors have, un- 
fortunately, too often been advised to use formol (formalin of 
commerce, a 40 per cent, solution of formaldehyde). The 
objection to formol for preserving fishes is that the tissues are 
stiffened to such an extent, even if a weak solution (5 per 
cent, of formalin) be used, as to render the manipulations 
necessary for description or study very difficult : in counting 
fin-rays and in examining the teeth and gill-arches, the fins and 
parts of the head break and specimens which seemed at first 
excellently preserved are soon damaged, which is all the more 
VoLc I. — No, 2. 
G 
