194 



BIOLOGICAL LECTURES. 



position short lengths of fine glass wire were passed through 

 the axis of each at different levels. A stock, therefore, of such 

 o-lass wire of varying thickness should always be at hand. 



For setting out dissected parts separately, pure plate mica, 

 white silk thread, a few fine needles, and ribbon pins are requi- 

 site. Equipped with the above, the botanist is ready for 

 nearly every object that presents itself. 



{b) Selection of objects. — The judicious selection of an 

 object is of supreme importance, and cannot be left to the 

 discrimination of any ordinary laboratory worker. It requires 

 the best judgment of the skilled botanist. By this we mean 

 that, while any one can gather a specimen and place it in a 

 jar of alcohol, only the expert can select such an example as 

 will epitomize details, and thus give permanent value to it as a 

 museum object worthy of study. In choosing each specimen, 

 then, the aim should be to learn how much can be judiciously 

 displayed and how many points advantageously shown ; for a 

 multiplicity of detail may only bewilder the student. This 

 notwithstanding, the amount of information that a well-selected 

 specimen can convey is astonishing. Take, for example, this 

 preparation of Larkspur {Delphinium Ajacis) gathered three 

 days ago from a garden near by. On looking round the bed I 

 found, that of the plants in bloom, only one had a good flower- 

 ino- branch — that now shown — which deserved preservation. 

 But an intelligent study of it is instructive. The lowermost 

 flowers have withered, but each has left a maturing follicle, 

 which in one example has been cut transversely, in another 

 longitudinally, to expose the rows of sporangia or ovules. Of 

 the six that are in bloom, four have been left entire ; but the 

 others have been cut in longitudinal and transverse section, so 

 that the shape and relationship of sepals, petals, stamens, and 

 carpel are evident. The uppermost flowers illustrate how the 

 floral leaves are folded in bud. 



Look again at this specimen of Vitis Labrusca. From nu- 

 merous flowering shoots that seemed all equally good, that 

 now shown was selected. The lowermost axis is tendriliform 

 and has clasped an oak twig ; the next above is in part tendrili- 

 form, in part flower-bearing ; the uppermost is an inflorescence 



