HAREWICKE'S SCIENCE-GOSSIP. 



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and which are figured, and described in the portfolio 

 are the following : — Vegetable Kingdom : Drapar- 

 naldia glomerata, Cfuvtophora elegans, Chara and 

 Nitella, Chara fragilis (embryo). Animal Kingdom : 

 Actinosphcerium Eichhornil, Coleps kirtus, Urostyla 

 grandis, Dinobryon sertularia, Vorticella chloro- 

 stigma, Anunca longispina and Ceratium longicorne, 

 Melicerta ringens, Lacinularia socialis, Alcyonella 

 fungosa, Bowerbankia gracillima, Bosmina longiros- 

 tris, Larval Shrimp, and Nais proboscidca, &c. 



The Microscopical Preparation of Sponges. 

 — In a paper communicated to the "Annals and 

 Magazine of Natural History," Mr. Sollas makes the 

 following remarks on the microscopical preparation 

 of sponges dredged by the Rev. A. M. Norman, on the 

 coast of Norway, for microscopical examination : — 

 "In preparing specimens for microscopical examina- 

 tion, I followed the ordinary methods for obtaining 

 the spicules in a free state ; but in cutting and moun- 

 ting 'sections,' I adopted the processes which 

 have hitherto, in this country at least, been confined 

 to the examination of quite soft tissues. A piece was 

 cut from the sponge large enough to contain a re- 

 presentation of each of its different tissues ; this was 

 then soaked in distilled water till its contained 

 alcohol was as nearly as possible all extracted ; it was 

 then transferred to a strong solution of gum, in which 

 it was allowed to stand for an hour or so ; finally it 

 was placed in the well of a freezing microtome, and 

 frozen in the usual way. From the frozen specimen, 

 slices could be cut of any required thinness, the razor, 

 strange to say, passing through the soft tissues and 

 hard spicules with apparently equal ease. The slices 

 so obtained were variously treated ; some stained and 

 some not, were mounted in glycerine of various 

 degrees of strength ; others were treated first with 

 absolute alcohol, then with carbolic acid and turpen- 

 tine and mounted in Canada balsam. • Teasing' was 

 resorted to in the case of some tissues with success, 

 especially when it was found desirable to observe 

 the behaviour of the tissue with reagents. Altogether 

 the various methods pursued have, 1 believe, suc- 

 ceeded in eliciting nearly all the information that 

 could be extracted from the specimens ; and that 

 this is very far from being so complete as could be 

 wished is to a great extent owing to the imperfect 

 manner in which histological characters are exhibited 

 in sponges which have been preserved in spirits with- 

 out any previous treatment. Mr. Norman's specimens 

 are perfect as spirit specimens ; they were not pre- 

 served with a view to submitting them to detailed 

 histological examination. And here it may be worth 

 while suggesting that if in the future it should be 

 desired to preserve sponges with this object, a 

 preliminary soaking in osmic acid solution of '02 or 

 •03 per cent, should be given to them before placing 

 them in spirits ; this will effect nearly everything that 

 may be desired. With osmic acid treated specimens 



and the help of a freezing microtome, no difficulty 

 should be experienced in obtaining an almost com- 

 plete knowledge of the minute structure of any 

 sponge." 



Trichinium Manglesii. — This lovely everlasting 

 flower, a native of Western Australia, has surround- 

 ing each floret, long glistening white hairs. These 

 delicate structures are prettily marked] and jointed, 

 each joint having teeth, reminding one of the stems 

 of the Equiseta. They contrast with the brilliant 

 purple of the petals, and under the microscope, 

 viewed by the aid of the parabolic illuminator, they 

 are very beautiful, and should have a place in any 

 collection of vegetable hairs. To those of the readers 

 of Science-Gossip who may not possess a specimen, 

 I shall be glad to furnish one on application. — 

 M. Medhurst, 2A, Dell Street, Holt Road, Liverpool. 



The Postal Microscopical Society. — It is 

 now some years since this society was formed, which 

 in its origin owed much to correspondence in the 

 pages of Science-Gossip. It has now gained a 

 good foothold and is well established, numbering at 

 the present time about 156 members, who reside in 

 various parts of Great Britain and Ireland. In looking 

 over the list of names I notice that the members are 

 not uniformly distributed, but are sometimes found 

 closely congregated in limited districts, which fact 

 is owing, I presume, to the influence of energetic 

 microscopists inducing others to become members. 

 I am therefore led to believe that the advantages of 

 this society are either not known sufficiently, or are 

 entirely unknown by many lovers of this very en- 

 chanting study. Any person (ladies are especially 

 welcome) interested in microscopy may join the 

 society by the following simple process. A proposal 

 paper has to be signed by a member and sent to the 

 honorary secretary. The would-be member may 

 obtain a list of the members and rules of the society 

 by applying to Mr. Alfred Allen, 1 Cambridge place, 

 Bath, who is at once the honorary secretary, and 

 the machinery of the society. New members on 

 joining the society are required to pay an entrance fee 

 of S s -> an d an annual sum of $s., which latter is due 

 on the 1st of October in each year. Members should 

 receive by post every fortnight a box containing 

 twelve slides, which may be kept three days, and then 

 sent by post to the next person named in the way- 

 bill accompanying it. There is also sent a MS. book 

 in which every member is requested to write some- 

 thing of interest relating to the slides in the box ; 

 drawings in further illustration of the slides are added, 

 but sometimes these do not appear so often as might 

 be desired. Not oftener than once a year each member 

 is required to insert one slide in each of four boxes, 

 notice of which event is always given beforehand 

 by the honorary secretary. Additional slides may 

 occasionally be required, but occasion for such addi- 

 tion should not often occur. The slides in general 



