150 



SCIENCE-GOSSIP. 



[Aug. 1, 1865. 



" sea-caff,"— probably implying " cliaff," something 

 waste and worthless (figs. 13, 14) ; but they have 

 in general no better designations for the numerous 

 tribe of zoophytes than "sea-weeds," "flowers," or 

 simply "growth." It is in the Flustra hispida, though 

 amongst the most common and apparently worthless 

 objects on the rocks, that the eye of the naturalist 

 has detected beauties and maiTels. Nay, on the 

 common Fucus serratiis, or " sea-ware," dark brown, 

 consistent-like, gelatinous patches are frequently 

 found on one or both sides of the leaf, occasionally 

 also encircling the stem. Sometimes these occur in 

 such profusion that the leaf is weighed dovvu by 

 them, or if reft from its site, feels heavy in the 



Fig. 13. Sea-mat. Fig. 14. Portion of gea-mat, 



magnified. 



hand. What, then, are these excrescences ? The 

 numerous inequalities of the surface, both to the 

 naked eye and viewed by a magnifier, offer some 

 resemblance to artificial manufactm-e, and in some 

 measure justify the name of "rough sea-mat." 

 Another zoophyte of the Meditemanean Sea passes 

 by the same name, but does not correspond in form. 

 But to recur to the wonders of the Flustra liispida. 

 Plimged amidst recent sea-water during genial 

 temperature, a pale thin cloud will speedily be 

 interposed betwixt its dark irregular surface and 

 the spectator's eye ; but on the vessel receiving it 

 sustaining a shock, this cloud is instantaneously 

 dispelled, whilst the brownish fleshy substance of 

 the Flustra remains prominent as before. This 

 illusion may be frequently repeated, for the cloudy 

 semblance is produced by hjdrfp, drawn from the 

 cells into which they had retreated, to revel in the 



freshness of the renovated element — and the misty 

 shade is caused by the motion of their pale tentacles 

 over the dark ground of the Flustra. So timid and 

 endowed with caution are these minute and active 

 beings, that they sink into concealment on the 

 apprehension of danger, and show by their re- 

 appearance their relief from alarm. 



But I must proceed no further with this very 

 incomplete notice of a large and interesting group 

 of the wonders of " the deep, deep sea." As cast 

 upon the shore the polypidoms are usually only the 

 uninhabited houses, the inmates dead, and their 

 remains dispersed ; but even the untenanted habita- 

 tions are well worthy a little minute examination, 

 and the living zoophytes will afford a world of 

 delight to the microscopist, and while away many a 

 weary hour of a lounge at the sea-shore. 



THE DIET OE WORMS. 



ll/rANY persons are not aware of the fact, that 

 -^-^ the earthworm really docs live upon earth. 

 It is sometimes stated in popular works on zoology 

 that the worm picks out portions of leaves, grass, 

 &c., and devours them; but this is quite a mistake 

 —the earthworm lives upon earth. It must not be 

 supposed that it assimilates the mineral constituents 

 of the soil; its gastric and biliary secretions dis- 

 solve the decomposing animal and vegetable matters 

 which are invariably contained in rich soil, and it is 

 these which are assimilated. The earthworm could 

 not live upon earth that had been burnt and de- 

 prived of its organic constituents. In a similar 

 way the arenicola, or lug-worm, which lives in the 

 sands exposed by the action of the tide, gorges 

 itself with that substance, and extracts the matters 

 which it contains fit for nutriment. More fre- 

 quently, however, the "lug" lives in the rich clays 

 of creeks and saltings which abound in animal and 

 vegetable matters. It is worthy of observation 

 that a very large quantity of earth or sand, as the 

 case may be, has to be gorged before any appreci- 

 able amount of nutriment is extracted ; at the same 

 time the swallowing of earth is an assistance to the 

 worm as it burrows in the ground, inasmuch as 

 large quantities of material are thereby removed 

 from its path and ejected behind. The appearance 

 of those curious little masses of digested earth on 

 the surface is thus caused, by means of which the 

 earthworm effects such wonderful changes on the 

 surface of the ground, turning up the earth, bmy- 

 ing the stones, and producing a fresh and fertile soil 

 where formerly was a barren waste. The mode in 

 which the earthworm swallows the earth is some- 

 what curious : its pharynx is extremely muscular, 

 and provided with an internal muscular tunic, which 

 acts within like the piston of an air-pump; anything 

 to which the mouth is applied is thus sucked in 

 and passed on by the action of the muscular walls of 



