5124 Fishes. 



The Millers Thumb in Confinement. — Early in the present year Mr. Hall brought 

 me a miller's thumb or river bullhead (Cotlus Gobio), the first I ever had the oppor- 

 tunity of watching. These little fishes are so abundant in the streams of Hereford- 

 shire that I have often found a dozen in my net at once when fishing for water-beetles, 

 but in our London waters they seldom tfcrn up: this is on account of the preference 

 which the miller's thumb has for clear running streams with a stony bottom. Like the 

 beardie, the miller's thumb is a fish that always lies at the bottom ; it has no power of 

 sustained swimming, and never suspends itself in the water like a true swimming fish, 

 but it will occasionally make a forced march to the surface, working its enormous 

 pectorals with great vigour and great labour, and sometimes such efforts extend even 

 to a tour of the globe or vessel in which it is kept, but after such extraordinary exer- 

 tions it sinks down, apparently exhausted, to the bottom, and there for hours remains 

 motionless. There is something very remarkable in the changes of colour which this 

 fish undergoes ; and these changes do not appear referrible to the ordinary tendeucy 

 which the colour of certain fishes has to assimilate with the colour of the surface on 

 which they are lying, but extraneous causes produce the effect : the swallowing a worm, 

 the effort of a swimming adventure, and, on one occasion, the extrusion of ova, have 

 produced such changes that the fish could not have been recognised under its altered 

 aspect: the colours are various shades of gray and brown, and these are sometimes 

 homogeneous, sometimes varied with great distinctness and brilliancy. Soon after this 

 fish came into my possession I observed its abdomen begin to swell, as though gorged 

 with food, of which it partook very freely, eating worms and raw meat with great 

 avidity. This swelling continued to increase until it seemed most oppressive to the 

 fish, which appeared continually gasping for breath. On the morning of Good Friday 

 these symptoms were explained : it had extruded during the night a mass of ova, col- 

 lectively equal in size to a sparrow's egg, and each individual ovum was about the size 

 the egg of Helix hortensis, and, like that, nearly transparent and enclosed in a tough 

 envelope : the mass was closely adherent, somewhat reminding one of frog's spawn, 

 but the ova appeared to have no mucilaginous covering. The number of ova must 

 have been about a hundred: of course I proposed counting and measuring them, in 

 order that I might favour the readers of the 'Zoologist' with exact statistics on these 

 heads, but two mornings after their extrusion I found the unnatural parent had torn 

 the mass asunder, and devoured the greater part of the ova, and before night the work 

 of demolition was completed by the combined efforts of the miller's thumb and two 

 minnows. — Edward Newman. 



What is Gasterosteus pungitius, and have we that Fish in Britain P — The problem 

 thus proposed for solution has to be considered from several points of view: 1st, from 

 the point of priority, of course I would adopt the Linnean version of the subject, pro- 

 vided a, that I clearly comprehended his meaning, and b, that I was as clearly con- 

 vinced that his was not a collective species, but I doubt on both these points, and reserve 

 tliem for further consideration. I will refer, in the first place, to Cuvier, and 

 quote every word of his description : — " L'Epinochette (G. pungitius, Lin.) est notre 

 plus petit poissou d'eau douce. Kile a sur le dos neuf epines toutes fort courtes ; les 

 cotes de sa queue ont des ecailles enrenees" (Regne Animal, ii. 170). In the ' Fishes 

 of Scandinavia' (pi. iv. fig. 2), is figured, under name of G. pungitius, a Gasterosteus 

 having nine spines on the back, and coloured red about the lower jaw, cheeks, gill- 

 cover and base of the pectoral. I have to regret that my ignorance of the Swedish 

 language prevents my understanding a single word of the description, but the plates 



