April 1, 1SG7.] 



HARDWICKE'S SCIENCE-GOSSIP. 



87 



had two hives of bees, stand included, knocked 

 clown to her for six shillings. Some of our old- 

 fashioned auctioneers demand a shilling per head 

 for all live stock, as a sort of deposit, and no sooner 

 did the hammer fall, than the auctioneer, a merry 

 old fellow, and almost as fat as Daniel Lambert, 

 demanded from the old woman a shilling a piece for 

 every bee in the hives. But he got his answer in- 

 stantly, "Then yo' mun count 'em." 



The pretty rye brome-grass (Bromus secalinus) and 

 the Darnel (Lolium temulentum) are both very com- 

 mon in some parts of Cheshire. The former is 

 known by the name of " Drook." A labourer once 

 told me that Drook was degenerated oats, and as a 

 convincing proof said that it was only found growing 

 amongst that grain, and that Darnel was degene- 

 rated wheat, and was never found amongst oats, 

 but I do not know whether this bebef is very 

 general in Cheshire. I could not persuade him that 

 he was mistaken, but a very little observation would 

 at least have shown him that drook is quite common 

 amongst wheat, and darnel amongst oats. Our 

 labourers, although they have nature's works con- 

 stantly spread out before their eyes, only distinguish 

 plants (unless it may be medicinal ones) by very 

 superficial characters; but they may be pardoned 

 for thinking that a drooping panicle of brome-grass 

 is somewhat akin to oats, and the stiff spike of 

 grain-bearing darnel is related to wheat. 



Robert Holland. 



STICKLEBACK IN SALT WATER. 



FN answer to your correspondent E. S., I have 

 -*- myself tried simdar experiments last year on 

 both the three and ten-spined Sticklebacks, and 

 found both species alike would live and thrive in 

 salt as well as fresh water. I was induced to try 

 these experiments from having obtained several 

 full-grown specimens of the three-spined out of the 

 sea in shrimp-nets (vide Couch), which in two cases 

 were full of well-matured roe, but never met with 

 a ten-spined one under those circumstances. There 

 are several small streams which contain these fish, 

 running into the sea, and probably they were thus 

 carried down. 



But the last part of your correspondent's letter 

 deserves much attention and close investigation as 

 of much interest to ichthyologists. I shall not pre- 

 tend or presume to offer any opinion on Ihe subject, 

 but will submit for consideration the following re- 

 marks : — Let it be taken for granted that all true 

 fish breathe through gills, that is, life is supported 

 by the blood being renovated by coming in contact 

 with the oxygen contained in the water, by means 

 of innumerable laminae on the surface of the gills. 

 Such being granted, 



I. Why do most fresh-water fish die in salt water, 

 and vice versa ? 



II. Why can a few of each sort live equally well 

 in either? 



1. In the case of fresh-water fish. Submitted :— 

 Cannot the component parts of salt water, or par- 

 ticles of the different salts, so affect the gills that 

 they get incrusted (if I may use the word) there- 

 with, and thus prevent the required amount of oxy- 

 gen coming in contact with the blood ? Or, is it 

 not possible that the blood itself may become im- 

 pregnated with saline particles, which prove fatal 

 to life ? or, if impossible for such salts to enter thus 

 into the system, may not these particles on coming 

 in contact with the gills, decompose and unite w r ith 

 the oxygen, and thus cause death ?— Next, as to 

 salt-water fish dying in fresh water. May not the 

 very absence or want of these salts in the system 

 destroy life ? or, the action of these soluble particles 

 on the laminae may cause a muscular irritability 

 indispensable for the exhaustion of oxygen, and if 

 deprived of which the active principle ceases, and 

 death ensues ? 



2. Where fish live in either fresh or salt water, 

 such as the salmon, stickleback, eel, mullet, &c, is 

 it not possible that with these and a few others, 

 they may have the power of disengaging or throwing 

 off those salts from the gills when exposed to their 

 action ? or, if admitted into the system, absorb them 

 without functional derangement ? Or else, will the 

 salt-water fish, when deprived of these salts, be able 

 to exert more muscular power and increased re- 

 spiration, and thus obtain the necessary supply of 

 oxygen ? 



I am aware that objections may be raised to 

 placing the above-named fish under the same cate- 

 gory, as the salmon and eel are essentially nugatory 

 and require both conditions for their well-being, 

 whereas the mullet is a salt and the stickleback a 

 fresh-water fish. But I have done so advisedly, to 

 bring under notice the difficulties (at least to me) of 

 fixing a theory where different conditions have to 

 be brought under the question— "How do these 

 fish live in either water without visible inconve- 

 nience?" Might not the microscope reveal that 

 the gills of different species of fish vary ; and, if so, 

 even in an infinitesimal degree, taking into consider- 

 ation the immense area exposed to the action of the 

 water,* that variation might produce entire change 

 in the natural economy of the fish ? 



Again. Has the blood of those fish now under 

 consideration been analysed; and if not, might it 

 not tend to show if any or what salts are necessary 

 to the one, absent in another, or present or absent 

 in the migratory ones at the period of migration to 

 and from the sea ? 



Bridlington. H. H. Knocker, R.N. 



* Mr. Couch says the surface of the whole gills of a large 

 skate is equal to 2,250 square inches, or more than fifteen 

 square feet. 



