CHAPTER OF VARIETIES. 



543 



has changed materially. No two conditions can be supposed more opposite 

 than the herling presents, when fed on salmon food, and when fed on 

 fishes. They differ, therefore, from salmon-trout in this respect : that, 

 when feeding on the food of the salmon, they attain almost the flavour 

 of the salmon, which the salmon-trout never does. 



The author discovered and exhibited the food of the vendace of 

 Lochmaben, which had never been seen before by any one ; explained 

 the reasons why this fish could not be taken with bait ; proved the 

 vendace to be male and female, and offers suggestions for the stocking 

 of the various lakes in Britain with this exquisite fish, pointing out 

 first the necessity of locating its natural food, without which it cannot 

 live. The discovery of these circumstances, with regard to the vendace, 

 led the author immediately to think of the herring, whose food and 

 natural history generally he believed to be unknown. 



It was ascertained that the herring resembles the vendace in its 

 habits, as to food more particularly ; and that whilst feeding on the 

 incredibly minute entomostraceous animals, which it more especially 

 affects, the condition of the herring is excellent, rendering it an ex- 

 tremely desirable food for man. In this state, the stomach seems as if 

 almost altogether empty (as in the vendace), though at the moment full 

 of minute animals, to be discovered only with the microscope, and on 

 which the animal has been feeding. The intestines also seem as if 

 empty ; the tunics of the whole digestive canal are fine and semi- 

 transparent, and as free of intestinal and putrescent debris found in 

 the stomach and intestines of animals, as if the herring actually fed on 

 nothing but air and water. When he approaches the shores, thus 

 quitting the proper feeding-ground, he takes to other and coarser food ; 

 his condition alters, and his flesh becomes soft and tasteless. The 

 stomach and intestines are found loaded with putrescent remains, and 

 gutted or ungutted, this fish could never be brought into the market 

 as equal to the product of the Dutch fisheries. 



The libellula, or dragon-fly. — " He," says Dr. Leach, " who 

 neglects the study of insects, or thinks it beneath his notice, cannot 

 deserve our respect as a general observer of nature, or be considered 

 as a scientific naturalist." A few observations upon one of the most 

 beautiful of the British insects cannot, therefore, be considered unim- 

 portant. The dragon-fly is by no means an uncommon insect in 

 England. The situations where it is most commonly found are near 

 the water's edge, sporting amongst the flags ; in pasture lands, and in 



