1897] Review — Life-Histories of Fishes. 143 



The authors' reference to Mcintosh and Prince's researches 

 as attempting for Teleostean fishes what the accompHshed 

 Francis Balfour did for the sharks has been objected to by Prof. 

 Lankester on the ground that the mere sketching and descrip- 

 tion of coloured lari'al fishes is not embryology at any rate is 

 not morphological. It is, however, precisely because the study 

 and sketching of these translucent young fishes, in which the 

 form and growth of almost every organ can be studied, that it is 

 morphological in the truest sense, and had the critic himself 

 ever studied from the egg onward the development of a fish, he 

 would not have committed so gross an error in criticism. 



There are few living workers to whom biological science 

 owes more than to Professor Mcintosh, and it is not too much 

 to say that his elaborate ichthyological investigations have over- 

 turned all preconceived notions respecting the life and char- 

 acteristic features of young fishes. It had been long imagined 

 that when hatched out from the egg, a young fish resembled its 

 parents, and that if the fry of various species could be obtained 

 they could be easily recognized. The caterpillar and ]iupa of a 

 butterfly were wholly unlike the perfect insect, and the young of 

 the most familiar fishes passed through stages of life in which they 

 did not resemble the adult fish with which we were all familiar. 

 The salmon, herring, cod, halibut and other well-known kinds of 

 fishes may be said to pass through at least four stages, viz., the 

 larval, late larval, post larval and final condition ; in the last they 

 resemble their parents, but are of very small size. Few fishes 

 when hatched bear any likeness to the full-grown condition, and 

 these are generally viviparous. Most fishes deposit eggs, and 

 from such eggs there emerge in due time minute creatures, 

 generally very transparent with large head and long tail and in- 

 commoded by a ponderous ball of yolk attached to their under 

 side. In a later stage the yolk is gone and the breast fins and 

 long fin on the back and tail are fully grown. Later, the breast 



