1?8 



KNOWLEDGE 



May, 1911. 



sliould he done as far as possible at one sitting. The 

 bones should be taken and arranged on a card. 



O 



or, better still, on the blackened glass sheet, in their 

 respective natural positions, the different regions 

 being spaced distinctly. The skeleton should be 

 mounted in a similar fashion on stiff" card which has 

 first been carefully blackened with a dull pigment 

 (such as ivorv black) as seen in the illustrations, and 

 thoroughly dried. A good method is to paint red lines 

 around or between the different regions. I would 

 advocate mounting all one's skeletons on the same 

 plan, and I think that the best is that shown in the 

 accom[>an\ing figures (1 and 2). It is mapped out 

 thus: — 



Lower Jaw 



and 

 Hyoideal 



Face 



and 

 Cranium. 



Hand. I'ore limb. Pectoral Girdle. Fore limb. 



Hand. 



C 

 e 

 r 



V 



i 

 c 

 a 

 1 



t 

 o 



S 

 a 

 c 

 r 

 a 



V 

 e 

 r 

 t 

 e 

 b 

 r 

 a 

 e 



C 



a 



F Hind limb. Hip u Girdk-. Hind limb. F 



o d o 



o a o 



1 



V 

 e 



r 

 1 

 c 

 b 

 r 

 a 



The bones on cither side are to be plared show iiig 

 inferior and superior surfaces respectiveh-, so as to dis- 

 play the various markings, and so on. The mounting 



is done with a fine camel-hau- brush dipped in 

 benzol solution of Canada balsam. This should not 

 be too stiff or a skin will form before the bone can 

 set : nor must it be too thin, or it will soak into the 

 bone and discolour it. In mounting the bone, it is 

 held in position abo\e the card by the forceps, and 

 the brush is drawn over the card so that it leaves a 

 film of balsam as near the shape and dimensions of 

 the bone as possible, on which the latter is then 

 dropped. (_)nlv sufficient balsam should be used 

 to ensure the bone remaining on the card, 

 and care should be taken not to soil the forceps 

 with the mucilage, or the marks of the bones may be 

 masked. The specimen is now placed in a box into 

 which the card fits exactly, and is kept in a horizontal 

 position. The preparation is now complete save for 

 the dr\'ing of the balsam, which takes a week or 

 two. 



Regarding the jireparation of skeletons of larger 

 animals, little need be added to what has already 

 been said. The bodies may, however, be boiled 

 with less risk, and both in cleaning and bleaching, 

 caustic potash may be used at discretion. A tooth 

 brush and nail brush are necessary for cleaning, and 

 the knife may be used more free!}-. 



The mounting, however, of larger preparations 

 differs considerablv from that ahead}' described. 



The bones, except the vertebrae, hands and feet, 

 should be left loose. Those of the hands and feet 

 should lie mounted on black cards, unless they are 

 large, when they should be bored and strung on 

 catgut in their proper positions. The best instru- 

 ment for boring is a "fiddle drill" such as is used 

 1)\- jewellers. The skeleton should be kept in a 

 box and di\iileil up into regions as before, each 

 region being placed in a separate partition for easy 

 reference. 



For larger animals, it is useful to keej) twn skulls, 

 one articulate and one disarticulated. To dis- 

 articulate the skull, it is first cleaned, and all the 

 brain matter removed with a scoop. The cranium 

 is then filled through the Foramen Magnum with 

 raw rice or dried peas, according to the size of the 

 foramina in the skull, and the Foramen Magnum 

 plugged tightly with a cork. The whole is then 

 placed in cold water in a saucepan and boiled until 

 the grain, by swelling, has forced the bones apart at 

 the sutures. The bones are then taken out, washed 

 and bleached. 



It is sometimes useful to keej) cartilaginous 

 structures. To retain these in their original shape 

 is difficult, in fact, almost impossible. The most 

 satisfactory method of preparing them is to dissect 

 them : clean : place in good methylated spirit for 

 twehe hours : soak in moderately thick solution of 

 Canada balsam for at least three days : and then 

 allow them to drv hard. 



1 \\:i\v purposely refrained from any description 

 of the methods of articulating skeletons. This work 

 would require an article to itself, and is unsuitable 

 to the beginner. 



