and Laboratory Methods. 



1837 



sessed of sufficient mechanical skill to make good preparations with the aid of 

 a few suggestions and a little oversight at the outset. And the practice is also 

 one of the best ways of gaining ground in the science of osteology, of so much 

 interest in the comparative anatomy of the vertebrates. The present article is a 

 statement of the experiences, chiefly those of Mr. Tyrrell, a student in Hamline 

 University, who has successfully prepared a considerable number of skeletons of 

 both birds and mammals. It is presupposed that the reader will have access to 

 one or more mounted skeletons of some good firm, for example, that of H. A. 

 Ward of Rochester, New York. Two of Mr. Tyrrell's skeletons are shown in 

 Figs. 1 and 2. The first is a porcupine from the Philippine Islands. It was 

 a rough dried skeleton when he took hold of it. The other is a sea gull. Both 

 are " articulated skeletons," that is, the natural ligaments still hold most of the 

 bones together. 



Fig. 1. — Skeleton of Philippine Porcupine. 



The first step, after cataloguing the subject and attaching a metal tag with 

 the number stamped on it to a convenient part, is to remove the skin. This is 

 usually done completely, that is, to the tips of the fingers, from the head, etc. 

 We have, however, in some cases departed a little from the traditions at this 

 point and retain the skin on one of the front and one of the hind feet of mam- 

 mals and on the leg and foot of a bird, and the wing feathers as well. This 

 shows in Fig. 2 ; in that instance the skin of the tarsus, the webbing of the 

 toes, and the relation of the primary and secondary feathers of the wing to the 

 bone of the arm are shown, thereby adding much to the value of the preparation 

 for the purposes of instruction. After the removal of the skin, the viscera are to 

 be removed and the inner walls of the abdominal and thoracic cavities picked 

 moderately clean. A pair of surgical forceps is used to reach the deeper places. 



