( S7 ) 



IV. — The Eggs and Larvce of Teleosteans. By J. T. Cunningham, B.A. 



(Plates I.-VII.) 



(Read 5th July 1886.) 



The purpose of this memoir is (1) to make known a number of drawings and 

 descriptions of the eggs, embryos, and larvse of the species of Teleosteans which 

 I have been able to study at the Scottish Marine Station ; (2) to review as 

 comprehensively as possible what is known at the present time concerning the 

 structure of the embryos and larvse of the species of Teleosteans, and to discover 

 what features are common to each family or each order; (3) to discuss the changes 

 which take place in the protoplasm and nucleus of the mature ovum immedi- 

 ately after it is shed, both when fertilised and when unfertilised. The ova of 

 the following species were taken directly from the parent fish, and artificially 

 fertilised. The necessary operations were carried out, in some cases by myself, 

 on board fishing boats — usually steam trawlers from Granton. In many 

 instances I did not myself go out in the boats, but the ova were obtained and 

 brought to me at the laboratory by Alexander Turbyne, keeper of the 

 station. But in every case there is no uncertainty as to the species of the fish 

 from which the ova were taken; if there was any doubt, specimens of the 

 parent fish were brought with the ova. 



1. Clupea harengus, Linn. (Herring) (PI. I. figs. 1-3). 



The development of the herring has been described by Prof. C. Kupffer* 

 in an elaborate memoir, which is illustrated by microscopic photographs. 

 Among these, one figure of the hatched larva is given, but this is on too small 

 a scale to exhibit the structure clearly. It is nearly two years since I studied 

 the ova of the herring, and some of the drawings which I then made have been 

 used to illustrate papers on particular problems in Teleostean development. t 

 But, as far as I am aware, no good figures of the larva of the herring have been 

 published, and I therefore think that the figures on PI. I. will not be super- 

 fluous. Herring, as is well known, have two spawning seasons on the east 

 coast of Britain — one in the spring, in February and March, and one in the 



* Ueber Laichen und Entwicklung des Ostsee-Herings, Berlin, 1878. 



t "On the Significance of Kupffer's Vesicle," &c, Quart. Jour. Micr. Sci., 1885; and "On 

 Kelations of Yolk to Gastrula," &c, Ibid. 



VOL. XXXIII. PART I. N 



