THE HAMILTON ASSOCIATION. 



85 



HAMILTON SPONCxES. 



BY A. E. WALKER. 



During the winter I have had a number of our SiUcious sponges 

 cut and poUshed in order to get a more perfect understanding of their 

 skeletal structure, and to work out the form of the spicules. They 

 have been sent to Professors Zittle and Rauff, of Bonn, Germany, 

 who are writing a special work on these forms, which will be beauti- 

 fully illustrated. All the Niagara sponges will be classified, and 

 those not named will be described and named. The plates follow- 

 ing illustrate a few of the pronounced forms. 



NO. 



No. I This plate gives a vertical section of one of the 



Aulocopina, showing the osculum from the upper opening to where 

 it is broken at the base. 



