121 



Aquatic kitt 



of service in identifying larvae. They 

 reach a large size before transforming 

 and probably spend two years in the 

 larval The breeding period is probably 

 in the early spring, and the transforma- 

 tion takes place in the late spring and 

 early summer. 



Around Philadelphia they are likely to 

 be confused with the larvae of the Two- 

 lined Salamander, Spelcrpcs bilineatus. 

 These reach 70 mm. before transforma- 

 tion, and adults of 48 mm. have been 

 found. Larvae ruber reach no mm. 

 and adults of 80 mm. have been noted. 



The smallest positively identified ruber 

 I have are 50 mm. long. In comparison 

 with bilineatus larvae of the same size 

 they are much more uniformly dark. 

 Larvae of bilineatus always have two 

 rows of large light spots on the back. In 

 ruber the spots are few and very small. 

 In bilineatus at 50 mm. the pigment 

 for the lateral dark lines has begun to 

 collect on the sides of these light spots, 

 thus showing an approach to the adult 

 coloration. 



At 79 mm. ruber is much more robust 

 than bilineatus, and its coloration is the 

 same as at 50 mm., while bilineatus shows 

 a much closer approximation to the adult, 

 in fact 70 mm. is an extreme length for 

 larval bilineatus and few reach it. Ruber 

 generally transforms at a length of 90 

 mm. External conditions, however, mod- 

 ify the size at transformation. 



In regard to keeping ruber in the aqua- 

 rinni, I can only say that it is very hardy 

 and will live indefinitely with little or no 

 care. The larvae will live best in very 

 shallow water. I have never tried keep- 

 ing them in balanced aquaria. The adults 

 should have easy egress from the water. 



To convince yon must believe. 



A rolling stone gathers no moss, and, 

 011 the other hand, no rnst either. 



British Aquarium Society 



A meeting of the above Society was held 

 at 4, Fetter-lane, on Friday, January 21. 

 The chair was occupied by the president, 

 Mr. W. T. Webster, F. R. M. S. A letter 

 from the editor of Country Life, in which 

 he related his experience in regard to fish 

 taking mosquito pupae as food, was read 

 by the President. 



The principal business of the meeting 

 was a lecture, illustrated by lantern slides, 

 on "British Fresh Water Leeches," by 

 Mr. H. Whitehead, B. Sc, of the Essex 

 County Museum. The natural feeling 

 towards leeches is one of repulsion, due, 

 probably, to its reputation for blood-suck- 

 ing. It was comforting then to hear that 

 the medicinal leech is the only British spe- 

 cies which is able to pierce the skin of 

 mammals. Of the fourteen species found 

 in Great Britain, three only are marine, 

 and eleven are found in fresh water. Of 

 the British fresh water leeches, only two 

 species attack fresh water fish — (Pisci- 

 cola gcometra and Hcinlclepsls margin- 

 ata) — a point of special interest to mem- 

 bers of this society. Others prey upon 

 worms, aquatic larvae, newts, frogs and 

 sickly fish. The young leeches have many 

 enemies, among which are moles, shrews, 

 voles, hedgehogs, ducks, storks and 

 herons. Certain fish, and aquatic larvae 

 (Hydro philus) do a great deal of damage. 

 Their own kind attack them, and even the 

 harmless snail-leeches suck them when 

 tender. 



All leeches are hermaphrodite, but 

 self-fertilization does not take place. The 

 eggs are carried in the clitellnm which, 

 when deposited, forms a cocoon. 



By the aid of an interesting lantern 

 slide, the leech was compared and con- 

 trasted with the earthworm. Fresh water 

 leeches are found in ponds and streams, 

 under the leaves of planks, and under 

 Concluded on page 12$ 



