836" ON THE GESTATION OF THE PINE-MARTEN. [Dec. 4, 



five days when in an embryonic state and left the nest in eighteen 

 days. Soon after hatching the larva was provided with gi'eat 

 bunches of protruding gill-filaments, which hung down as a blood- 

 red beard. The yolk-sac became drawn out into a long cylindrical 

 bag, which was completely absorbed by the time the larva left the 

 nest. The larvae while in the nest continually came to the surface 

 and took air into the lung-like swim -bladder. 



The nests of Heterotis nitotieus were also found. These were 

 built on the swamp-bottom in two feet of water. They measured 

 four feet across the walls reaching the surface of the water. The 

 fish was observed making its nest, which, when finished, was 

 perfectly round and quite smooth. The larva? soon after hatching 

 formed a swarm in the centre of the nest, and were at that stage 

 provided with long protruding gill-filaments. 



Another remarkable fish, Sarcodaces odoe Bl., was found breeding 

 in the same swamps. It laid its eggs in masses of foam, which 

 floated on the surface of the water. The hatched larvae were 

 provided with adhesive structures on the front of the head, with 

 which they hung to the underside of the surface. 



Nests were also found containing eggs which apparently belonged 

 to Hyperopisus bebe Lacep., one of the Mormyridce. These nests 

 were scooped out from the swamp-bottom ; the eggs were attached 

 to the rootlets thus laid bare. The hatched larvae were provided 

 with six cement-glands on the surface of the head : by these a 

 delicate rope of mucus was spun, often nearly the length of the body 

 of the larva, by which the larva hung suspended from the rootlets 

 until the yolk-sac was absorbed. 



This paper will be printed entire in the Society's ' Transactions.' 



The following papers were read : — 



1. Note on the Gestation of the Pine-Marten. 

 By A. H. Cocks, F.Z.S. 



[Keceived AuguBt 21, 1900.] 



Pine-Martens {Mustela martes) first bred in my collection in 

 1882, a note on which was published in the ' Zoologist ' for 1883, 

 p. 203. Various details concerning the ra<:e of growth of the 

 young were recorded, including the interesting fact, which seems 

 to have been previously unsuspected, that the young are at first 

 perfectly white. Since then other litters of this species have been 

 bred in my collection ; but as we never could discover when the 

 female came in season (and have never even yet seen this species 

 pairiug), all attempts at breeding were extremely hazardous : the 

 allowing of a pair to run together was apt to result in the death 

 of the female, in consequence of one or more of the long canines 

 of the male penetrating her brain, the damage being inflicted so 

 instantaneously that there was no possibility of a timely separation. 



At last, this year, we noticed little mouthfuls of short straw 



