256 



HAilDWlCKE'S SCIENCE-GOSSIP. 



algse. In one of the hot springs of the Californian 

 Geysers, Dr, Blake also found two species of 

 confervse, at a temperature of 198° P. In another 

 spring, at a temperature of I7'ii° P., he met with 

 various Oscillarife, the interlacement of whose 

 fibres formed a semi-gelatinous mass. Two species 

 of diatoms were also found in the same place. In 

 the water of the Creek of Geyser Canon, at a 

 temperature of 112°, the algse formed layers three 

 inches thick, which covered the bottoms of the 

 pools. The waters are acidulated by the presence 

 of free sulphuric acid, and Dr. Blake thinks that 

 this may account for the rarity of diatoms. 



Preparing Slides. — For the benefit of your 

 numerous readers who desire to become acquainted 

 with a clean, ready, and easy method of preparing 

 slides, applicableto fresh cuticles, insects, c%c., where 

 heat (as in the case of Canada balsam) is quite inad- 

 missible, I 'beg to forward you the formula for a 

 medium, discovered and used by myself with great 

 success. Take of clear Dammar resin five drachms ; 

 benzine, one fluid ounce. Dissolve without heat. 

 Modus operandi : — Place a drop on the slide, put 

 the object upon it, let fall another drop upon the 

 object, and apply the cover. The fluid that escapes, 

 on pressing down, when pressure is necessary, will 

 speedily harden, and the object may be at once 

 examined in any position. In the course of ten 

 days it may be cleaned and placed in the cabinet. 

 Objects prepared for the polariscope are especially 

 brilliant in this medium. An additional advantage 

 possessed by it is, the trifling expense incurred in 

 its preparation. — Saml. Smith. 



A Singular Botifee.. — In tlie last number of 

 the Quarterly Jotirnal of Microscopical Science, 

 Dr. Hudson makes known a rotifer, under the name 

 of Pedalion mira, having six large appendages like 

 the limbs of a crustacean, terminating in plumose 

 hairs, and worked as locomotive organs by trans- 

 versely striped muscles attached inside the appen- 

 dages, which are therefore hollow, and identical 

 in type with the limbs of insects and Crustacea. 

 At the same time, the animal possesses a fine 

 ciliated trochal disc, and a gizzard similar to that 

 of other rotifers. Specimens had been supplied 

 to t!ie editor; who confirms the statements of 

 Dr. Hudson in every particular. 



On the Microscopic Preparation of Insects' 

 Eyes. — Good preparations which shall demonstrate 

 clearly the structure of insects' eyes are very much 

 wanted in this country, and, as far as I know, 

 almost impossible to obtain ; yet such are com- 

 paratively easy toprepare, and, when well made,form 

 objects not only admirable for class demonstration, 

 but are extremely beautiful in themselves. The 

 eye of a large Sphinx moth is most easily prepared; 

 best of all, that of Acherontia atropos ; but Sphinx 

 Ucjustri will do very well. The moth should be 



killed and the head placed immediately in absolute 

 alcohol. After it has been in alcohol about a week, 

 it should be taken out, imbedded in a mixture of 

 wax and oil, which should be rather hard, in order 

 to offer plenty of resistance to displacement when 

 the glutinous parts are cut through. The sections 

 should be floated on to slides stained with car- 

 mine, heated with absolute alcohol oil of cloves, 

 and mounted in Dammar varnish or Canada balsam. 

 The great thing is to use plenty of absolute alcohol 

 and a thin-edged, hollowed-out razor. If the heads 

 of smaller moths be used, sections very instructive 

 may be prepared, passing through both eyes and 

 the cephalic ganglia. Preparations of the eyes of 

 mollusca, leeches, &c., may be prepared in tiie same 

 way as those of insects, from specimens hardened 

 in the same manner in absolute alchohol. — //. N. 

 Moseley, M.A., in Quarterly Microscopic Journal. 



Microscopical Troughs. — Many microscopists 

 have, no doubt, felt the want of a small trough for 

 use with powers of —o or \. I have constructed 

 and used for some two years the one of which I 

 inclose a drawing, and find even a fifth can be 

 used with it, there being no thick glass to obscure 

 the definition of the objective. Should any of your 

 readers not be able to make this themselves, I have 

 given Mr. Crouch a drawing of it, who will, no 

 doubt, be glad to supply them. An ordinary glass 



Fig. 182. Microscopical Trough. 



slide with half-circle cut out, and thin glass ce- 

 mented on back and front, either of a semicii-cular 

 shape, as dotted lines at B, or of an oblong form 

 as C ; or the lower thin glass can be made of length 

 of slide, insuring a true level, as at D.— /. IF. 

 Meachen. 



Auditory Capsules op Mollusca.— Mr. Fulla- 

 gar, at a meeting of the East Kent Natural History 

 Socict}', called the attention of the members to a 

 very beautiful aud interesting object, viz., — the 

 auditory vesicle and its vibrating otolith of Cyclas 

 cornea. Tliis beautiful object is very easily found. 

 Mr. Eullagar, after two or three trials, by tearing 

 asunder witii needles portions near the base of the 

 creature's foot, succeeded in showing the vesicle 

 and otolith, much to the admiration of the meeting. 



Vertebrate Blood Corpuscles. — A number of 

 models have been prepared by Ilerr J. Klautsch, 

 assistant in the Anatomical Institute of Halle, 

 illustrating the relative dimensions of the red 

 corpuscle in various vertebrata. All the models arc 



