124 IOWA ACADEMY OF SCIENCES. 



LABORATORY NOTES IN ZOOLOGY. 



HERBERT OSBORN. 



It is my purpose, in these notes, to call attention to some matters of 

 experience in laboratory work which may be of service to other teachers 

 and also to place on record the results of some studies by students that 

 appear to be worthy of pi-eservation. 



Laboratory work in zoology has been carried on at the Agricultural 

 College since 1876, and for nearly all of that time under my own super- 

 vision, so that while my own specialty has kept me busy in other lines some 

 notes from the experience of these years may be of service to teachers who 

 may be situated in similar localities. It is needless to suggest that work in 

 an inland laboratory will naturally take somewhat different lines than a 

 seaside laboratory. 



We first began the use of marine material in our laboratory about ten 

 years ago and at that time there was but one place where material suitably 

 prepared and at prices consistent with laboratory work could be secured. 

 Now a number of seaside laboratories as well as individual collectors fur- 

 nish excellent material and no laboratory need want in this direction. 

 Hydroids, starfishes, sea urchins and squids seem most essential as repre- 

 sentatives of groups unknown away from the sea coast. The ease with 

 which such material may now be had, the full treatment of these types in 

 various guides and convenience of dissection may, however, almost be 

 considered a danger as it may tend to the neglect of our common inland 

 forms which it may, possibly, be a little more inconvenient to secure just 

 at the time they are wanted. I believe we should be careful to avoid this 

 danger, for students, especially those who may become teachers themselves, 

 should be impressed with the fact that material for study is available at any 

 point, and so far as they may be representatives of the groups to be studied, 

 the species close at hand should be used. 



The protozoans ai'e of course available in every stagnant pool, but it is 

 sometimes desirable to be sure of abundant supply of amoeba and other 

 forms at a certain time, and this may be accomplished by keeping the con- 

 tents of jars over from year to year, allowing them to dry up before winter 

 or when not in use. For a number of years I kept a particular block of 

 wood that furnished amceba regularly for a number of different classes. It 

 was allowed to dry in autumn, the ooze with which it was coated of course 

 remaining, and then two or three weeks before the material was wanted the 

 jar in which it was kept was partly filled with water, and in due time an 

 abundant crop of amoebie could be secured. 



