HARDWICKE'S SCIENCE-GOSSIP. 



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on account of the peculiar spines on the plates of its 

 arms. This species is found only in the older rocks, 

 such as the Caradoc beds at Bala, on the west side of 

 the beautiful lake. At Benson's Knot, Docker Park, 

 and other places near Kendal, in Westmoreland, 

 where the upper Ludlow rocks crop out and quarries 

 are opened in them, a student may expect to find 

 Palasterina primava, and Uraster Ruthveni, the 

 latter named after one of the most diligent and devoted 

 of amateur geologists that ever lived. Both the latter 

 fossils belong to the same group as our modern " five- 

 fingers," and they have been beautifully preserved 

 (as any one may see, who pays a visit to the Kendal 

 Museum), in spite of the skin being only thickened 

 and not plated, with calcareous spicules. Two 

 species of fossil star-fishes have been found rather 

 plentifully in the Cambrian rocks at Welshpool, 

 Meifod, and Corwen. Next we come to the Lias 

 strata for abundant star-fishes, and we have seen 

 that one bed is especially rich in them. The Liassic 

 species usually belong to the "brittle-stars," and the 

 commonest of these fossils is Ophiolepis Egertoui, 

 found at Staithe, near Whitby ; and also abundantly 

 in various places in Dorsetshire, especially at 

 Seaborne. Specimens of this star-fish may be seen 

 in nearly every museum in England. 



The marginal plates or ossicles of star-fishes allied 

 to the cushion-stars (Goniaster), are not uncommon 

 in the Chalk, and in the flints which come from that 

 deposit. In the chalk quarries atGravesend, Charlton, 

 many places in Kent and Sussex, as well as Norfolk 

 (particularly about Norwich) remains of these Echino- 

 derms may be found, but only by practised eyes. 

 We have seen perfect specimens imbedded in the flint 

 nodules obtained from Ipswich and Norwich. In the 

 London Clay of the Isle of Sheppey we find similar 

 remains of Goniasters ; ossicles, plates, &c, in a more 

 or less perfectly preserved condition. 



We should be glad to hear from any of our geo- 

 logical correspondents further details respecting the 

 " star-fish bed " in the Lias— its locality, extension, 

 species, &c. ; and, indeed, concerning any fossil star- 

 fish locality. 



MICROSCOPY. 



EUGLENA VIRIDIS AND ITS SUCKER-BULB.— I am 



glad to note further confirmatory evidence in your 

 columns with reference to the existence of a bulb or 

 sucker at the extremity of flagellum in Euglena viridis, 

 and may further remark that Mr. George Harkus 

 notes a central darkening or marking, indicating a 

 tubular structure in this organ (this gentleman's 

 sketches were enclosed to the Editor with original 

 query, and no doubt their accuracy would be observed). 

 Will Mr. F. Jas. George say if he has detected the 

 bulbous termination in all examples, or only in those 

 obtained from special localities ? In some quarters the 



statement of its existence has been received somewhat 

 dubiously, but this may arise from the certain fact 

 that only an objective of the best defining and re- 

 solving power will determine it. We (Mr. Harkus 

 and I) found a Ross quarter inch, and a Swift's eighth 

 to work well upon it, an immersion sixteenth had not 

 sufficient penetration, but still revealed the bulbs 

 coarsely. Perhaps the following observation may 

 explain to your correspondent how the Euglena 

 became metamorphosed into rotifers. Last autumn 

 I obtained from a pond Euglena sanguined in pro- 

 fusion. Griffiths and Henfrey regard this as the 

 perfect form of Euglena viridis : the gathering was 

 placed in a vessel covered with a sheet of glass, and 

 in a few weeks assumed the still or protococcoid form, 

 gradually in this interval changing in colour from 

 red to green, the whole mass sunk to the bottom of 

 the vessel, and during the winter continued to 

 segment and increase by division, until now a portion 

 lias reverted to the Euglena viridis in its motile form, 

 this confirms the opinion of authorities named above. 

 I can substantiate Mr. F. Jas. George's remark, 

 that the place of the Euglena ' ' was taken by the 

 common Funnel Rotifer." In my experiment, I find 

 a fine and most interesting variety of rotifers, but 

 I also invariably see the internal cavity of these 

 individuals well stocked with what may be regarded 

 as the zoospores, into which Euglena in its still con- 

 dition segments, divides, and then breaks up. In 

 fact these rotifers subsist upon Euglena. Could it be 

 shown that Euglena was the larva of anything, the 

 question of its animalism would of course be settled ; 

 will the existence of the bulb siphon, sucker, or what- 

 ever it is, assist in determining it ? — M. H. Robson, 

 Newcastle-upon- Tyne. 



A New Method of Preserving Infusoria. 

 — Would T. C. kindly furnish more particulars of the 

 mixing solutions ? I do not understand what he means 

 by chromic oxydichloride acid. Is it dichloride of 

 chromium ? I have some of this in solution saturated 

 and slightly acid ; but he does not state the strength 

 or percentage either of this or of the permanganate 

 of potash, so that I am puzzled to know how to mix 

 it.— T. B. 



Microscopic Cleanliness. — Amongst the many 

 difficulties with which the working microscopist is 

 surrounded, none (in a small way) is more general 

 and annoying than the difficulty he experiences in 

 keeping his hands perfectly clean. Let him be as 

 particular and careful as he may, stains of balsam, 

 pigments and varnishes, and smears of the thousand 

 and one sticky and discolouring materials with which 

 he has to deal will get upon his fingers, and to 

 remove them he often finds to be a matter involving 

 much time and trouble. Soap and water won't touch 

 them, ether is expensive, and turpentine or benzole 

 is dirty and offensive in smell. Mr. Archer, of 

 Liverpool, has recently patented a small slab or block 



