416 

 2. The Academy of Natural Sciences of Philadelphia. 



June 23rd, 1896. — Rev. H. C. McCook, DD. reported a series of 

 observations on the California Trap-door Spider, Cteniza calif arnica , made 

 by Dr. Davidson who had been able to determine the time required for the 

 construction of the burrow in confinement and other matters connected with 

 the life-history of the animal. It had taken ten hours to construct the nest 

 with its hinged door, another spider having made a hole large enough to 

 conceal itself in two hours. The method of digging was the same in the main 

 as that described by the speaker for the tarantula. The young when they 

 emerge at once build their own miniature nests which are renewed every 

 spring until they reach the full size. Based on the study of a Lycosid the 

 speaker had predicted that the enemy of the trap- door spider would be found 

 to be a diurnal wasp. Dr. Davidson had established the fact that such is the 

 case and that the attacking species is Parapompilus planatus Fox. — Mr. H. 

 C. Mercer made a report on his recent exploration of certain caves in 

 Tennessee which he had been able to prosecute under the patronage of the 

 University of Pennsylvania, mainly through the liberality of Dr. William 

 Pepper. In Zirkel's cave on Dumpling Creek, Jefferson County, Tennessee, 

 crusts of breccia projected from the walls and hung from the roof. From 

 this material the teeth of the tapir, peccary, etc. projected, while in the cave 

 earth below were found bones, nuts, two pieces of Indian pottery and frag- 

 ments of mica, probably indicating Indian cave burial. There were, there- 

 fore, two ages indicated; one ancient by the breccia, and the other, the cave 

 earth, comparatively recent. All the fossil remains belonged to the breccia 

 and there was no association between them and the indications of human 

 life. Another cave on the Tennessee River, under Lookout Mountain, Ha- 

 milton County, Tennessee, presented a floor of two layers, the black top 

 one of three or three and a half feet in thickness composed of Indian re- 

 mains and another of yellow earth containing a few animal remains but no 

 indication of human existence. Mylodon and Tapirus fragments found 

 sometime ago close to the bottom of the upper layer had probably been 

 scraped up from the lower. Neither, therefore, did this cave present any certain 

 data for the advancement of the date of Man's antiquity. On the contrary 

 the evidence supported the belief that pleistocene or paleolithic Man had 

 not existed in that region. On penetrating the forbidding entrance of Big 

 Bone Cave, near Caney Fork River, Van Buren County, Tennessee he had 

 found nine hundred feet in, the bones of Megalonyx still bearing articular 

 cartilages. Fragments of torches were found beneath the sloth bones prob- 

 ably buried by burrowing rats. — Prof. E. D. Cope commented on the fossil 

 bones collected in the caves described by Mr. Mercer. The presence of car- 

 tileges on the Megalonyx bones indicated for them an age certainly not more 

 remote than the existence of Man on this continent. Other bones belonging 

 to young individuals were larger than corresponding ones found at Port 

 Kennedy indicating the validity of the two species: Megalonyx W/ieaileyi and. 

 M. Jeffersonii. Mr. Mercer had also collected remains of fifteen or twenty 

 species of birds, six fishes, one batrachian, four tortoises, one rattlesnake 

 and nineteen mammals. The special value of Mr. Mercer's careful work 

 was commented on. The peccary is found in Zirkel's cave although no trace 

 it appears in the Lookout Mountain cave. Several undescribed species were 

 indicated. 



Drnck von üreitkopf A Hartel in Leipzig. 



