SCIENCn-GOSS//' 



4.> 



<lfpo>iis arc fiirinirig. These have received the name 

 of Oozes. Accordirn; to the predominalinf; con- 

 ".litiienl, these oozes are known as C.loliigerina Ooze 

 or I'leropiKl Ooze. It is but fair ti> sny that all the 

 <lc|;osits, whether the most prominent type of organism 

 lie the one i>r the other, also contain in v.irying pro- 

 portions either other /■'oraniiiii/ern, molluscs, or 

 calcareous a!,i;ae (seaweeds). In some places, the 

 ooze assumes a ilifl'erent character. In the Antarctic 

 Ocean, and in other areas where there is a relatively 

 low specific gravity, the de|xjsil was found to consist 

 chiefly of the microscopic frustules of diatoms. As 

 these vegetable organisms are chemically of a 

 silicious nature, we have here what is known as a 

 Silicious Ooze. This, we may imagine, was in 

 cretaceous times a partial source of the silica, after- 

 wards deposited as flint. Nor was this the only 

 silicious ooze, .\nother order, belonging to the class 

 Khizopoda, to which it will be remembered the 

 For:in\inifera belong, is the Radiolaria. Kepre- 

 seniatives of this order were so numerous in an area 

 in the Middle and Western I'.icilic that they 

 constituted a Kadiolarian Ooze. The Kadiolaria 



bear a close resemblance to the Koraminifera, 

 but differ from them in the fact that 

 their little globules of olive-brown sarcodc 

 are enclosefi in beautiful glassy tests com|)oscd of 

 silica, instead of carbonate of lime, and these are 

 often most delicately sculptured and chased. Here, 

 then, we also have an ooze of a silicious nature. 

 flalioiiima, a member of the radiolarian order of the 

 I'olycystiuae, was a common form foimd in the ooze. 

 It possessed a spherical test or shell, with numerous 

 holes through which the pseudopodia were emitted, 

 and the test was often adorned with spines. A 

 newly-discovered family lias received the name of 

 Challengeridae, most of its members possessing purse- 

 shaped silicious shells, with one or more openings, 

 and freipiently being ornamented with pit like 

 markings. 



The deep-sea oozes are as follows : — 



(i. ) Calcareous: (n) Globigerina Ooze; (//) Plero- 

 pod Ooze. 



(ii.) Silicious: (a) Diatom Ooze: (/') K.idiolarian 

 Ooze. 



(Jo l>c (oiiliniiiti.) 



SUBSPOXTAXEOUS MOSSES. 



Hy J. .\. WiiKi.iiciN. 



AMON<;ST the accepted natural integers of the 

 flora of any given district, we constantly meet 

 with strangers which have become accidentally 

 mingled with the true natives. These, according to 

 their permanence and mode of introduction are 

 variously classed as aliens, casuals; denizens, or 

 colonists. I.n most of our local floras the status of 

 our flowering plants is carefully worked out, but 

 amongst the smaller cryptogams it is very seldom 

 that any attempt is made to determine whether the 

 species are native or otherwise. These more obscure 

 plants are usually accepted as aboriginal inhabitants, 

 and probably rightly so in the majority of instances. 



It is, however, certain that introductions must 

 constantly occur, although it is seldom easy to prove 

 that they are importations. The common species are 

 continu.iUy reinforced liy immigrants, which probably 

 arrive as spores in soil, conveyed in various ways by 

 man and other animals, or by the wind. The 

 growing plants themselves may also be brought in 

 with earth at the roots of introduced trees and plants, 

 or may be transptprted on stones and tree trunks from 

 place to place by human agency or floods. 



Perhaps iminigrants received l>y some of these 

 methiwls should hardly be considered as casuals, the 

 means of introduction being quite natural. To take 

 an example, Ciiiiiiiiolns Joiilhiahhiis can hardly bo 

 classed under any category except that of native, 

 when it occurs spor.idically in the lower reaches of the 

 river Ouse about York. Vet it is obviously not at 

 home, and only maintains a precarious existence 

 there. Its occurrence is no doubt brought aliout 



accidentally by flooils and violent spates of the Yore 

 and .Swale, in the upper reaches of which it thrives 

 exceedingly. An exactly analagous case may be 

 quoted from the phaneroganiia. A'liiiicr aijiialitiis is 

 brought down by floods to Clifton Ings, in the same 

 manner, where it establishes itself for a lime, but if 

 not reinforced would probably soon disappear from the 

 banks of the Ouse. 



The occurrence of Pollia Itcimii in the grounds oi 

 St. Mari's .\bbey. at N'ork, was perhaps quite as 

 accidental a circumstance as that of Fissidcns 

 orrii in the vicinity of the Glasnevin Kotanical 

 Gardens. The same, I have but little doubt, 

 would apply to /iryiim iiiurale in many of 

 its recorded stations. In my own somewhat 

 limited experience of this rare moss, it usually aft'ects 

 the mortar of walls, and is very apt to disappear in a 

 short time ; so that in localities where it is fairly 

 plentiful one year it may not be found at all the next. 

 When so situated I look upon it as a mere casual, 

 notwithstanding that the specific name is bestowed on 

 account of its apparent predilection for such habitats. 

 In the .Mersey Province, its only natural home is on 

 the limestone scars of West Lancashire, where this 

 moss abounds in rock crevices about Silverdale, 

 Vealand, and Carnforth. Elsewhere in the Province 

 named, it occurs only (m walls, in isolated localities, 

 as at Fleetwood, Marple and IJromboro. Mr. 

 IJ.ignall notes it, again on walls, from a. single locality 

 in Staflordshire. Can any reader of SciE.NCtc-Gossii' 

 give another in.stance of the occurrence of this species 

 on rocks ? 



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