ORTMANN: THE CRAWEFISHES OF THE STATE OF PENNSYLVANIA 347 
The tools and the outfit needed for collecting crawfishes consist of rubber-boots 
(for work in swamps), or wading-stockings with low shoes (for work in streams), 
bayonet (for digging up burrowing species), and a landing-net with minnow-netting. 
These are indispensable. Further, a number of collecting jars are needed, with 75 
per cent. to 80 per cent. alcohol, and I prefer to carry them in an ordinary fishing- 
basket, but any other portable receptacle will do. I do not recommend the use of 
formaldehyde, since it makes the specimens too brittle. In order to take specimens 
home alive, a so-called ‘‘ bait-box”’ is most convenient. ; 
I have. no experience in baiting crawfish, and never attempted it, since the 
methods described above proved satisfactory. Furthermore, I have never (in 
Pennsylvania) used the seine, and I do not think that this would be necessary or 
advisable in this part of the country, although it may be tried to advantage else- 
where. 
Besides the material secured by me in the manner above related, | made use of 
the older material preserved in the Carnegie Museum, which was collected by the 
following gentlemen: D. A. Atkinson, G. H. Clapp, E. Frost, B. Graf, J. L. Graf, 
Hi. Hays, 8S. N. Rhoads, A. T. Shafer, Q. T. Shafer, H. H. Smith, R. Taylor, W. E. 
C. Todd, M. A. Wertheimer, and E. B. Williamson. 
I was aided in my researches by material kindly collected by various persons for 
the Museum, while my work was in progress, and to all of them I wish to here 
express my best thanks. They are the following members of the Museum staff: 
Mrs. Elizabeth Courtney, Mr. C. V. Hartman, Mr. D..C. Hughes, Mr. O. E. Jen- 
nings, and Mrs. O. E. Jennings. 
The following gentlemen living in or near Pittsburgh furnished|material : Dr. D. 
A. Atkinson, Dr. O. T. Cruikshank, Mr. R. Dornberger, Mr. D. Friel, Mr. F. E. 
Kelly, Dr. A. Koenig, Mr. A. Settlemoyer, and Mr. R. Settlemoyer. 
Material from other parts of Pennsylvania was received from Professor A. E. 
Davison, Lafayette College, Easton, and Mr. H. Gera, Manayunk. 
Specimens of our Pennsylvanian species were received from localities outside of 
the State from the following sources: Academy of Natural Sciences, Philadel- 
phia, (material from Delaware, Maryland, and North Carolina, in exchange); Mr. 
H. Gera, Manayunk, (material from New Jersey); the late Mr. J. B. Hatcher, Pitts- 
burgh, (material from Iowa); Mr. O. E. Jennings, Pittsburgh, (material from Ohio); 
Mr. 8. Prentice, Pittsburgh (material from Kansas); Dr. R. Ruedemann, Albany, 
New York, (material from New York); Mr. F. Silvester, Princeton, New Jersey, 
(material from Maryland); Mr. E. B. Williamson, Bluffton, Indiana, (material from 
Kentucky, Indiana, and Michigan). 
