618 



SCOMBEROID.E. 



" I. The first thing to be done is to pare away the 

 exterior rough bark with a cooper's spokeshave, or 

 other convenient tool ; this admits of a distinct in- 

 spection of the actual state of the trees, which, if there 

 is no trace in the inner bark either of small holes in 

 old trees, or of those superficial furrows which the 

 Scolyti make for food in young trees (and which may 

 be distinguished from the natural crevices in the bark 

 by their dark-coloured and dead margins), may be 

 pronounced to be in a sound and healthy state, and 

 requiring no further attention. 



" 2. If the inner bark exhibits either of the appear- 

 ances above mentioned, the next thing is to ascertain 

 whether the female has already deposited her eggs 

 in it ; and if it contains the larva? of the Srolyti, to 

 know which it is necessary to cut away portions here 

 and there of the bark down to the actual wood and 

 examine them ; and if the existence of the larvae be 

 proved, the trees should be cut down and their bark 

 peeled off, and every fragment of it carefully burnt. 



" 3. Those trees which, though pierced with exterior 

 superficial holes or furrows, have no larvse in them, 

 are such as have been attacked by the Scolyti for 

 food only ; and if they be carefully brushed over 

 with coal tar, the smell of which is highly offensive 

 to the perfect Scolyti, there is every probability that 

 they will be secure from the future attacks of the 

 females ; and that the repetition of the same process 

 in the spring for a year or two would enable them to 

 resume their vigour and to become healthy trees ; 

 for the future fate of which, if at the same time the 

 entire removal of all the trees actually diseased has 

 been attended to, there would be no need of appre- 

 hension. It is in this way, as we are informed by 

 Mr. Spence, that a great number of the young elm 

 trees on the boulevards of Brussels, brought into an 

 incipient state of debility by the attacks of the Scolyti 

 for food, but not yet attacked by the females, were 

 treated on the spring of 1836 with every prospect of 

 a successful result, though of course some years must 

 elapse before any absolute deductions can be drawn 

 from the experiment." 



In conclusion, we cannot but regret that the assist- 

 ance of some competent person was not required by 

 the Commissioners of Woods and Forests, previous to 

 the wholesale and indiscriminate felling of the trees 

 in Kensington Gardens, the ornament of the metro- 

 polis, which it will require so many years to replace, 

 where sound and unsound trees of other kinds have 

 been cut down to the ground. Let us hope, now 

 that the preceding observations have led the way to 

 a more precise acquaintance with the subject, that 

 the axe will be laid more sparingly to the trees which 

 still remain. 



SCOMBEROID^E the Mackarel family. The 

 seventh in order of the fifteen families into which 

 Cuvier arranges the Acanthopterygii, or spinous-finned 

 fishes, and one which in the number of its genera and 

 its species, the countless myriads of its individual 

 members, the vast numbers of them that are caught, 

 and the excellent qualities of the flesh of very many, 

 may be reckoned among the most interesting and 

 valuable of all the inhabitants of the ocean. They 

 are all fishes of great power in the water, swimming 

 with incredible energy, generally at no great depth, 

 and often appearing at the very surface, where many 

 of them display a brilliance, variety, and change of 

 colour, which defy all powers of description. Inha- 

 biting thus near the surface, they are fishes which 



breathe much more than those that live at a greater 

 depth, and thus they die more speedily when taken 

 out of their native element than those fishes which 

 have a slower action of the system, and inhabit further 

 down. It is a pretty general law too, that fishes (at 

 least bony fishes) which have rapid action and breathe 

 much, cannot be kept so long after they are taken 

 out of the water, as those in which the action is more 

 moderate. The mackarel family agree with the law 

 in this, and none does it more than the common 

 mackarel. No fish, obtainable in any thing like the 

 same quantity, is better than mackarel when perfectly 

 fresh, but there are few that sooner become tainted 

 and unwholesome. 



No sea that can be named is without one or other 

 of the members of this numerous family, and there 

 are seas in which a great variety of them are to be 

 met with. But even the outline of their history 

 would fill volumes, and therefore we can do nothing 

 more than indicate the leading genera, and mention 

 one or two of the species which are most interesting 

 to British readers. The family contains in all fifteen 

 leading genera ; but in many of these the species 

 differ so much from each other, or are so numerous, 

 that Cuvier, who had no disposition to make any 

 wanton increase of divisions in any part of the system, 

 found it necessary to subdivide them into more than 

 thirty subordinate genera, in addition to these leading 

 ones. 



The general characters of the family are : the sur- 

 face of the? body smooth, the scales small, the muscles 

 of the posterior part of the body, and the caudal fin 

 especially, very powerful. There is one part of their 

 muscular structure which is worthy of attention, as 

 showing the peculiar organisation of a fish which is 

 formed for getting rapidly through the water by mus- 

 cular action alone, without much assistance from the 

 resistance of raised posterior edges to the scales. 

 The flakes, as they are vulgarly called, are thicker ; 

 that is, they measure more in the direction of the 

 length of the body than they do in fishes that have 

 large scales, and especially than those which inhabit 

 lower down and have less powerful action in the 

 water. This admits of a greater length of the indi- 

 vidual muscular fibre ; and thus the contraction and 

 bend resulting from it are more rapid and more ex- 

 tended than if the fibres were shorter and there were 

 a greater number of them in the same length of the 

 body of the fish. Some members of the family are 

 without any air-bladder, and others have one, which 

 is one of the many proofs that this organ, what- 

 ever may be its use, is not absolutely indispensable 

 at any particular depth in the water, or for any par- 

 ticular rate of swimming. We shall now barely 

 enumerate the genera. 



SCOMBER (Mackarel properly so called). This, 

 which is the typical genus of the family, is sub- 

 divided into eight ; the first of which is, 



Scomber (the common mackarel). This is a fish 

 which every body knows ; and in the elegance of its 

 form, and the beauty of its colours, it is equalled by 

 few fishes. It of course partakes of the distinguish- 

 ing characters of the genus, the most obvious of which 

 are, the form of the second dorsal fin and the anal ; 

 these have some of their rays nearest the tail detached 

 and forming a series of processes which get the name 

 of false-fins. The characters more peculiarly descrip- 

 tive of the mackarel itself are : the body spindle- 

 shaped, or thick at the middle, and tapering to both 



