74 



HARDWICKE'S SCIENCE-GOSSIP. 



of bees in collecting pollen, rifling the flower, for this 

 "bee bread," and the no less precious nectar, thus 

 assisting in bringing the anther and stigma into 

 contact. This is common knowledge, but the asso- 

 ciation, although explainable on general theory (and 

 other instances of widely diverse but necessitous 

 dependencies exist), is strangely mysterious. Those 

 who have watched and who understand the necessities 

 of bees, cannot have failed to observe that their 

 eagerness for the collection of pollen comes exactly 

 at the right time, when storage for the nourishment 

 of the young larvae and the fructification of the plant 

 are coincident. Who has not seen the bee rolling in 

 the blossom and rifling the rich contents, leaving for 

 the hive with golden pellets stored in receptacles 

 on thighs (adapted for the very purpose), but con- 

 siders the influence of the importance of the insects 

 sweeping over the stigma of the plant, the few 

 fructifying uncollected grains ? It has been stated on 

 the best authority that one community of bees will 

 collect fifteen pounds' weight of pollen or "bee- 

 bread " in one season, 



" Brush'd from each anther's crown, the mealy gold. 

 With morning dew, the light-fang'd artists mould. 

 Fill with the foodful load, their hoUow'd thigh. 

 And to their nurselings bear the rich supply." 



To the fructification of the cryptogamous or flower- 

 less plants it is unnecessary to refer, beyond observ- 

 ing that the primary process is obscured to ordinary 

 vision, and requires for its revelation the highest 

 powers of the microscope. The whole of the repro- 

 ductive elements are involved in each individual 

 spore, or particle of " fern dust." Under favourable 

 circumstances these minute specks produce a grow- 

 ing expansion, " prothallus," in which is contained 

 a peculiar condition of cellular contact leading to the 

 development of the future plant. 



Prothalli may be produced or propagated by 

 strewing spores of ferns on a porous brick, kept 

 moistened with moderate warmth under a bell-glass, 

 and may, while growing, be arranged on glass slips 

 for microscopic observation under high powers. 

 Pollen grains and the adjacent parts retain their 

 form and position when carefully dried, and may 

 be conveniently seen t(as an opaque object) under 

 low powers, and easily mounted and preserved for 

 future reference and comparison. 



Crouch End. 



Geese Migrating. — Having seen a note in 

 Science-Gossip about geese migrating, it may in- 

 terest the writer to know that about a fortnight ago, 

 a flock of thirty-two geese was observed flying, very 

 high, over Wrenbury, Cheshire. They were flying 

 towards the north, leaving Combermere on their left, 

 in " single file," one of their number keeping a little 

 to the right, apparently a kind of " off-skirmislier " or 

 leader. They were cackling as they flew.— i)/, E. T. 



HOW TO KEEP SMALL MARINE 

 AQUARIA, 



'"T^HE difficulties, real and imaginary, that present 

 ■i- themselves in connection with marine aquaria 

 and the keeping of marine animals generally, often 

 deter the would-be marine zoologist from any further 

 attempt to retain life and health in a confined 

 tank, after his first experiment has terminated, as it 

 too often does, in decomposition and disaster. 



The following observations may therefore be of 

 some service in at any rate enabling others to do 

 what I have recently done, namely, to keep marine 

 animals in glass jars of only one pint or so 

 capacity, not only in a healthy condition, but that 

 too with little or no trouble, for a considerable time ; 

 the period in the case of my own jars being, as I 

 write this, just four months and a half. 



In the middle of October, 1883, I obtained a few 

 marine animals which I thought I would try and 

 keep alive for a short period ; my only receptacles at 

 the time were two glass bottles of something over 

 one pint capacity, with mouths about half the 

 diameter of the bottle. My stock of sea-water was 

 about two quarts. I put a pint of water into each of 

 the bottles, and placed a small stone in each, to 

 which were rooted nice small tufts of Ulva latissima. 

 In bottle No. I I introduced a full-grown mussel, 

 Mytihis edulis, and one winkle, Littorina littorea. 

 Into No. 2 I placed two beadle t anemones. 

 Actinia mescmhryanthemnni, one Actinoloba diaiithus 

 (small), three very young mussels and one winkle. 

 I placed the jars on a table close to a window which 

 faced due east, and covered the mouths each with a 

 small bell glass, which by resting upon the shoulders 

 of the bottles excluded all dust. The remainder of 

 the water I corked up in another bottle and kept it in 

 the dark. I commenced my care of these miniature 

 tanks by diligently syringing in order to aerate the 

 water ; it certainly did that, but it also broke off" 

 fragments of the algse, and in a few days things 

 began to look bad, and I had arrived at that stage 

 when the experiment is usually given up and the 

 decomposing mass is thrown away. However, 

 although the water was tainted and things were not 

 looking promising, I knew I had a reserve tank to 

 fall back upon, so I gave the bottles a good shake up 

 and poured off" the sea-water, which was full of bits, 

 and very dirty, replacing it with fresh sea-water. 

 The effect was miraculous; the anemones "came 

 out," the winkles resumed their travels, and once 

 more matters looked favourable. 



I then carefully strained the tainted water, which 

 even after that operation was very thick, and put it 

 into the reserve bottle, shaking it vigorously once a 

 day ; in about a week it had got quite clear again. 

 But to return to the jars ; there was no doubt that 

 syringing, as applied to pints of sea-water, was 

 simply courting failure, so I left jar No. I quite alone 



