On the Scales of Fishes. 247 



variation in the order of proceeding. But for the present our 

 inquiry is addressed to that kind of organization which we 

 designate a scale, and of which the intimate structure and 

 manner of growth have obtained little notice from naturalists, 

 although in their nature they are well worthy of inquiry. The 

 illustrious Cuvier had directed his attention to the subject, and 

 with some degree of success, as was certain to be the case with 

 whatever he took in hand. But it is apparent that his obser- 

 vations are not in all cases to be relied on j and from what 

 appears in the translation of his "Animal Kingdom," there 

 seems reason for believing that they were not made over a 

 wide extent of the families of fishes that had passed under his 

 notice. But the interest of this subject is such as to deserve 

 a more intimate examination ; and so much the rather, as in 

 its pursuit we may find it to assist us in ascertaining something 

 of the affinity of what might appear distantly removed species ; 

 and also it may point out some adequate explanation of the 

 fact, that some sorts of fishes, even in families well supplied with 

 this clothing, have them altogether concealed within a smooth 

 and soft skin, and others nearly related to them are altogether 

 destitute of them. In this latter case we may remark, that in 

 many instances the internal and external layer of the skin are 

 separated by a thickened layer of what may be termed a rete 

 mucosum, or soft cellular network ; in which case the surface 

 of the body remains moist for a longer period when it is 

 exposed to the air ; and this may be the cause why some fishes 

 are capable of living long when out of their native element. 

 Experiment has shown that there are fishes which speedily 

 become lighter in weight when exposed to air, while others 

 diminish but little. There is reason also for believing that if 

 some fishes, when out of the water — of which, as an instance, 

 some of the blennies may be mentioned — be frequently 

 wetted over the surface of the body, to the exclusion of the 

 gills, the skin alone will perform a function that shall long 

 sustain the life. It would even appear that such is the case 

 also with some fishes which cannot properly be said to be 

 without scales, although generally so regarded — as the common 

 eel, in which they lie embedGled beneath the surface, but are 

 visible on close inquiry, and of which a satisfactory magnified 

 representation is given in the Honourable Mrs. Ward's 

 " Microscope Teachings," PI. V., Pigs. 8, 9 ; but nothing 

 similar has been discovered in a fish so closely resembling it as 

 the common conger. It is in remarkable contrast with this 

 that the power, one of the Gadoid fishes, becomes deprived of 

 its scales very readily ; while the ling, which belongs to the 

 same family, is not furnished with scales, so far as we are able 

 to ascertain ; and the megrim, or scaldfish among the flat fishes 



