HARDWICKE'S SCIENCE-GOSSIP. 



185 



sanguinea is a splendid example of the latter, many 

 other algae are almost as striking. Our common sea 

 anemones and antheas present examples not only of 

 flower-shaped animals, but of animals with green 

 juices. Among the "commonest of all, the Actinia 

 mesembryajithemum, I have found every tint from 

 blood-red and dirty brown to delicate grass-green, 

 these colours residing more or less in the juices of the 

 animal. The Anthca viridis is of brilliant emerald 

 green with crimson-tipped tentacles. These are 

 specially abundant in the rock pools of Jersey. 



Mr. MacMunn found actual chlorophyll in nine 

 specimens of sea sponge ; Ray Lankester has found 

 the same in freshwater sponges. That which is found 

 in the Anthea cereus he attributes to symbiotic algae, 

 i.e. to vegetables living within the animal, not as 

 parasites, but as partners. Mr. Geddes some time 

 ?.go proposed to apply the generic name of Philozoon 

 to these unicellular plants. It appears that they 

 mutually co-operate, the expired oxygen of the plant 

 supplying the animal with material for respiration, 

 and the expired carbonic acid of the animal similarly 

 serving the vegetable. The green cells have been 

 transplanted from one animal into the body of 

 another, and have survived in symbiosis, as this 

 curious economical co-operation is named. 



NOTES ON THE ROTIFERA. 

 (A Prolific Pond.) 



EARLY last summer I was fortunate in discover- 

 ing a most remarkable pond — remarkable not 

 merely for the number, but also for the character of 

 the species of the Rotifera it has furnished me. I had 

 known the pond for years, and passed it scores of 

 times without giving it more than a casual glance, 

 and from the entire absence of visible vegetable 

 Jife, I assumed the absence of animal. Not even the 

 ubiquitous Anacharis was present, and I failed in 

 every attempt to find the humble Conferva, whose 

 spores might furnish food, and whose matted thread- 

 like fronds might give necessary shelter to micro- 

 scopic forms of animal life. It is an artificial pond, 

 situated on a level plot of ground, a portion of which 

 lias for some years been cultivated as a flower 

 garden, and there is an entire absence of trees or any 

 shade whatever. To some of the above circum- . 

 stances, and to the fact that, in order to get to it, it 

 would be necessary to trespass, and more to the fact 

 that in a long ditch or " goit " (which for a part of its 

 course is separated from the pond by about a yard of 

 earth, and two retaining walls below the level of the 

 ground), I had already a "happy hunting-ground," 

 I attribute my carelessness in not " fishing " the pond. 

 Early last summer, however, on arriving at my ditch, 

 I was dismayed to find that the water had been let 

 off, the plants had shrivelled up to mere ghosts of 



their former selves, and the exposed mud baked hard 

 and dry in the summer sun ; in despair I half turned 

 round on my heels, and as a forlorn hope plunged 

 my muslin net with quinine bottle attachment into 

 the crystal depths of the despised pond. Among 

 numerous minute worms, and jumping Entomostraca, 

 I could with pocket-lens detect many specimens of 

 Rotatorial life. Since then I have paid almost 

 weekly visits to the place, with the result tabulated 

 below. They are not arranged according to any 

 system of classification, but simply put down, with 

 one or two exceptions, in the order in which they 

 occurred. 



Brachionus rubens ; B. Bakeri ; B. urceolaris ; 

 B. a?igu!aris ; B. pa/a, and var. amphiceros ; Pterodina 

 patina ; Euchlanis triauetra ; E. dilatata ; E. oropha ; 

 Proales petromyzon ; yEcistes crystallinus ; Monura 

 dnlcis ; Fwxtclaria gracilis ; F. forficula ; F. micropus; 

 Triarthra mystacina ; Polyarthra platyptera ; Rotifer 

 macrurus ; R. vulgaris ; Philodina erythrophthalma ; 

 R hi tiops vitrea ; Coluras obtusus ; Monostyla lunaris ; 

 Syncheta tremula ; Floscularia cornuta ; Asplanchna 

 Brightwellii ; Diglcna forcipata ; Scaridium longi- 

 caudata ; Syncheta pectinata ; Notholca scapha ; 

 Diaschiza Hoodii ; D. tenuior ; D. exigua ; Colurus 

 caudatus ; Callidina elegans ; Rotifer tardus ; Limnias 

 ceratophilli ; Copeus cerberus. In all 38 species, 

 which are being added to almost weekly. With 

 regard to the number of species, it has, I believe, 

 been exceeded by only two recorded instances, that 

 of Miss Davies' pond, Woolstone, which yielded 44 ; 

 and another one of hers having 41 ; several others, 

 however, run it very close, viz. Dr. Collins'sold pond, 

 which yielded 36, and another of Miss Davies' which 

 yielded 35. It will be seen that many in my list 

 belong to the aristocracy of Rotatorial life, and not a 

 few of them to the very uppermost crust. Several 

 other forms have come under my notice, but as I 

 have not been able to study them sufficiently for 

 identification I omit them from the list. It will be 

 noticed that three of the above species belong to the 

 order Rhizota, and I ought perhaps to explain, that 

 in dredging, I do occasionally get a little Conferva, 

 which grows in small patches on the stones forming 

 the boundary wall, rather deep in the water, and it 

 is to this Conferva that the " root-footed " Rotifers 

 are attached. It is perhaps unfortunate, that I have 

 not kept as accurate an account of other forms of life 

 as I have of the Rotifera, because the pond is only 

 less remarkable for its Algae, its Infusoria and its 

 Entomostraca. Of Diatoms there are species of 

 Surirella, Encyonema, Synedra, Melosira, &c. Other 

 Algas, Pandorina, Cosmarium, Closterium (3 species), 

 and Pediastrum ; and Vaucheria, Spirogyra, Rivularia 

 and Draparnaldia among the Confervae. 



Infusoria, &c. — Amoeba, Actinophrys and Difflugia 

 (several species), also Savill Kent's Choano-flagellata ; 

 Loxophyllum, Trachelitis ovum, Spirostomum, Di- 

 leptus, Stentor, Ophrydium, Vorticella, Vaginicola 



