260 proceedings of the academy of [1884. 



October 21. 

 Mr. Thomas Meehan, Yiee-President, in the chair. 

 Twenty-nine persons present. 



The following papers were presented for publication : — 

 " On the Cuspidiform Petrogl^^phs, or so-called Bird-track 

 Rock-Sculptures, of Ohio," by D. G. Brinton, M. D. 



" Preliminary Observations on the Brain of Menopoma," by 

 Henry F. Osborn. 



October 28. 

 The President, Dr. Leidy, in the chair. 

 Thirty-nine persons present. 



Organisms in Ice. — Prof, Letdy stated that a member had 

 placed in his hands, for examination, a vial of water obtained from 

 melting ice which is used for cooling drinking-water. From 

 time to time, among some sediment taken from a water-cooler, 

 the gentleman had observed what he supposed to be living worms, 

 which he suspected were introduced with the water into the 

 cooler, and not with the ice. Upon melting some of the ice alone, 

 the worms were still observed, and the water submitted for 

 examination was some that was thus obtained. Prof. Leidy was 

 surprised to find a number of worms among some flocculent 

 sediment, mainly consisting of vegetal hairs and other debris. 

 Besides the worms, there were also immature Anguillulas, and a 

 number of Rotifer vulgar^is, all living. It would appear that 

 these animals had all been contained in the ice, and had been 

 liberated on melting. It was an unexpected source of contami- 

 nation of our drinking-water, that Prof. Leidy had previously 

 supposed to be very improbable. The little worms he was not 

 familiar with. 



They belong to the family of Lumbricidse, and probably may 

 be an undescribed species of Lumbriculus. They are white, or 

 colorless, from 4 to 6 millimeters long, by a third of a millimeter 

 in thickness. The body is divided into thirty segments, bearing 

 podal spines, which form four rows, with three in each fas- 

 ciculus, and divergeut. The spines are curved at the root, 

 pointed at the free end, and measure 0*05 to 0-06 mm. long. 

 The upper lip is blunt conical; the terminal segment truncate. 

 Tliere appears to be no distinct girdle, but the tliird, fourth, 

 and fifth f^egments contain capsuligenous glands and other organs 

 pertaining to the sexual appaiatus. 



Several dead worms swarmed in the interior with large, ovate, 

 beaked, ciliated infusorians measuring from 0-05 to 0*06 mm. long 

 by 0-04 to 0-048 mm. broad. 



