238 Mr Schonberg on the Spawn of Salmon. 



the hypothesis. This curious fact cannot fail to strike one as 

 a very wise dispensation of Providence ; for, when the eyes are 

 both placed in the front of the head, as in man, the circle of 

 accurate vision is extremely small, but whatever approaches 

 within the wide limits of indirect vision, particularly attracts 

 the attention by its expanded size, and gives a remarkably ex- 

 tended scope to our field of observation. 



July 1826. A 



Art. IX. — On the Spawn of Salmon, observed in its pro- 

 gressive State, and Drawn from Nature. By L. Schon- 

 berg, Esq. Communicated by the Author. With a Plate. 



The eggs or spawn of the salmon, represented in their natu- 

 ral state in Figs. 1 — 4>. Plate V., are of the size of a common 

 pea. Their colour is lively, and they are transparent, mixed 

 with yellowish brown and red. When they pass into whitish 

 red, and lose their transparency, they are of no use for experi- 

 ments, as they are then in a corrupted state. Few, indeed, 

 can be brought, or rather kept in a proper condition. Out of 

 nearly 200, four eggs only succeeded, however fresh their ap- 

 pearance at first was. Changing of the water, and, if possible, 

 from the same river, must be repeated hourly, and they must 

 likewise be exposed to the sun's influence. 



Fig. 1 . b. Shows a spawn magnified ; position of the fish 

 visible ; head joined with tail ; a large artery passing between 

 them ; point of pulsation very distinct, almost the day when 

 taken from the river. The animal moves itself now and then 

 with alternate contraction and dilatation. The spawn keeps 

 generally a fixed point of gravity, viz. eyes sideways : The eyes 

 are manifested by two gray-black spots, situated sideways 

 in the globe. The following day no motion perceptible ; the 

 day-light not strong enough to reflect upon the glass. Eyes 

 assuming the third day a white spot in its centre. 



Fig. 2. Shows the spawn in different positions, after the 

 head had made its way through the shell or egg ; this hap- 

 pened the fifth day. 



The spawn advanced to the state in Fig. 3. after a lapse of 

 eight hours. Tail twisted around a transparent substance, per- 



