70 INTRODUCTION. 



are wholly destitute of this feeling, and every other 

 which is in any way associated with it; that all their 

 emotions, cold as their blood, indicate only indi- 

 vidual wants and selfish propensities. That this 

 is generally true we do not mean to dispute; and, 

 in fact, it is not easy to conceive how any parental 

 regard can be exercised towards a progeny so nu- 

 merous as that which belongs to the majority of fish, 

 amounting, according to Mr. Jesse, to more than half 

 a million in the mackarel, to nearly a million and 

 a half in the flounder, and to 3,686,760 in the cod 

 (Gleanings, i. 90); and these ova evolved only after 

 having been buried in the sand or gravel for weeks 

 and months, or wafted about on the floating billow. 

 But while necessity thus, in the majority of cases, 

 compels this total abandonment of their progeny, 

 yet it is interesting to know that this practice is by 

 no means universal, and that instances are not rare 

 in which there is a clear manifestation of parental 

 instinct exhibited sometimes both by male and fe- 

 male, occasionally previous to the birth of the young, 

 by the preparation of a suitable receptacle, or nest ; 

 and at other times afterwards, when the fry are pe- 

 culiarly exposed to imminent hazard from the innu- 

 merable foes with which they are surrounded. We 

 rest this assertion not merely on what we have 

 had occasion to mention above regarding the Mar- 

 supial and the Obstetrical fishes, which, however, 

 pre-eminently belong to this category, but upon 

 others whose structure and habits are widely dif- 

 ferent. All of those to which we now proceed to 



