690 INSTRUCTION TO SCIENCE TEACHERS. 
the male and female gonophores, but the larval * planula-form” 
as it escaped from the reproductive capsules. Plumatella as a 
typical Bryozoon succeeded this, and then two days were given to 
the dissection and histology of Anodon, of which each student 
was provided with two or three specimens. The lobster as a 
typical Arthropod was then examined, a fresh specimen being | 
supplied to each table; the heart and vessels were first studied, 
then the alimentary canal, liver, reproductive organs and green 
glands. A large piece of mill-board covered with paper was used 
by each pair of students for placing out in order, numbering, 
naming and comparing the twenty somites and their appendages, 
an instructive preparation being thus made. The corresponding 
parts were again examined, and the microscopic structure of the 
muscular tissue, blood, liver, and gills, in specimens of the river 
cray-fish. The careful dissection of the frog next occupied some 
days and to this succeeded the rabbit. 
Simultaneously with the dissection of these vertebrata, the study 
of the microscopic structure of the various tissues and organs was 
commenced, so that whilst one student was using the microscope, 
his companion at the table was dissecting, and vice versa. The 
blood of the frog and of man}the movements of the colorless cor- 
puscles in both cases, and the action of acids on them, the varieties 
of epithelium, the various forms of connective tissue and its cor- 
puscles, cartilage, bone, muscular tissue smooth and striped, nerve 
fibres and cells, the termination of nerve in muscle, and the struc- 
ture of the more important organs, were examined by the class, 
not in already prepared and mounted “ slides,” but in specimens 
which each student took for himself, usually from the animal un- 
der dissection, and treated with various reagents, the methods of 
cutting thin sections and embedding tissues in wax or paraffin 
being learnt at the same time. 
A simple injecting apparatus (formed by two Wolff’s bottles and 
a large vessel of water) was put up, and the method of injecting & 
frog shown to each student. The best part of a day was spent in 
a thorough dissection of a sheep’s heart, and another in the dissec- 
tion of the sheep’s larynx. Vertical antero-posterior sections of 
the sheep’s head were supplied to the various tables, and in these 
the parts of the brain and cranial nerves (already made out in 
the rabbit), the tongue, the relations of the cavities of the mouth, 
nose, and ear, the ducts of the salivary glands, and the muscles of 
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