장음표시 사용
252쪽
254쪽
2. COIIecling. For the collection Os torri- and bryocolous Oribatids themost ideat apparatus is the Beri se funnei and iis severat modifications
1953, 1958, etc.). AII these devices are so universalty known that it is Superfluous to enlarge On them. Vet it must be mentioned that since their functioning is based on the principie of the gradual desiccation Of the soli samples, they frequently functiori but imperfectly in subtropical and tropicat areas where the humidity content of the atmosphere is Very high. HOMeVer, their effectivity may be increased eVen in such places by the use of large-siged
256쪽
3. It assures an ideat optical medium ;4. From the ΡOint of vlew of time, it is more economical than a temporary
os the most minute species Brachychthonius, Oppia, SuctobeIba will remain intact, - is the Berlege fluid under the cover glass is deeper than the height of the animal. The larger specimens will be crushed, in the majority of thecases, due to the diminishing fluid Iayer. Due to the evaporation of the Beries
fluid, the cover glasA Will so Oner Or later come into contact with the animal, and since most Oribatilis are either sphaerical Or cylindrical in form, thepressure Os the glass will bear On the dorsal furface On a giveri potnt Or alonga line. Because of the strong pressure thus exerted, the animal will he crushed, hec oming quite useless aster SO me time. This difficulty can in many cases beeliminat ed or at Ieast Iessened by an excellent process used by M. SELL ICK.
This author inseris thicli celluloide strips made of photographic filmin under
the coVer glaSA On twO Or ali four Os iis fides. The decrease in volume of th Boriose fluid due to evaporation will thus not aci directly on the animal ; tho
257쪽
I t e m 3. It is also indisputatile that the Berlese fluid, ΡVA. and all
259쪽
The a luantages os both methods may bc combined is we also make a collecti an os permanent mounts from Our duplicate materiai. It is sufficient tol luce a species into thiS collection On One Occasion Only, as this Will serve forcomparative PurPOSes. Ιf the preparations Will Alowly deteriorate with timo, Our collection suffers no lossos, and the Peri8hed mounts ean again be replacedisoni the duplicate materiai. 5. Τhe preparatiori and examinatiori methods of the author. I xvisti topoliat Out, sirst os ali, that there is esSentialty nothing ne v in the methoddiscussed helow. The Processes to be eXPO unded are, at least Parily, used by severat acarologisis so that I deviate from the usual at most in the combination of the vario iis methodS. Preparation and eXaminati an may be reduced to four phases :
4. Conservation, collection. Item 1. In essentiais, this consist8 in dissolving and remo ing, andas far as possibio completely, the in ner organs of the animal, - yet with th ut most care SO that the cuticular appendages, especialty the hairs, shouldr main uninjured. For this purpose, the generat use is to heat the animais in lactic acid. Heating takes generalty a se v minutes, just untii the laetio acidbegitis to steam. Thera tho animal can he examined ut Once. By the use of this method, the inner Organs dissolve biit partly undus ually will not leave the hody. Ther fore the microscopical picture is frequently not qui te clear. Animais troated in this Way are generalty fuit ahlosor identification, hiat not for an exact description, projection and draWing For this cause, I sorgo this method using inste ad the colit lactic acid proces on the advice of SELLNICK.
vials in largor ones containing the labet, pulting the whole material in a tight fit ting box or cubinet in a d ust-sree place, letting it Stand at ro Om temperaturo D P Dding on the fige of the animais and the thic kness of their chitin, I - 6 monilis are nee led for tho dissolution and the removat Of the tissues. Nordoes complete dissolution Occiar in ali cases, but even SO, tho uni mulS Rre moro transparent than those treat ud Solely by hea ting. Item 2. Thore is an absoluto Deed for depigmentation in the caseMos black or dark bro via species, as also in those of very large Ones vith tho
260쪽
in Atopochthonius GRANDI EA' 19483. Generally, however, the hairs rema in intaci and the animais Mill not depilate. FOr the elimination Os these injurios, it is ad vis able to deposit a part of the material in alcohol, the Other part in luctic acid without depigmentation, and to depigmentate those specimensonly which are nee led for eXamination. Depigmentation is hight y important in the systematic study of tho Oribatilis. There a re certain genera with very dark- coloured species Whichcannot be examine d and identisied ut ait without a proper depigmentation e. g. Carabodes, Liacarus, Achipteria, Galumnidae). Depigmentation affori sthe only means by whicli One can make adequale draWingS in these genera. I am convinced that the generat use of depigmentation wili considerat, lyincrease the accuracy os drawings and descriptions made Of Oriballiis, and
Item 3. The examination method most suit able for the stud y os