1903.] NATURAL SCIENCES OF PHILADELPHIA. 81 



The water evidently instigated her to the cocooning, yet in natural 

 conditions these spiders do not appear at all aquatic, for I have 

 found them on rather dry ground under stones and logs. 



The number of cocoons made, and the dates, were as follows: 



(1) 9 No. 183: June 11, hatched July .5. 



(2) ? No. 193: July 25, a failure. 



(3) ? No. 196: June 14, hatched July 10; July 2, a failure. Two 

 cocoons. 



(4) ? No. 197: June 12, dropped by the mother and did not hatch; 

 July 13, dropped also after the mother had bitten it open prematurely; 

 August 10, dropped August 30. Three cocoons. 



(5) 9 No. 203 was caught with a cocoon that hatched July 1. 



(6) 9 No. 214 was caught with a cocoon that hatched July 5. 



(7) 9 No. 268: July 20, a failure. 



Care of the Young. — As in other species of the genus, the cocoon 

 is carried by the mother attached to the spinnerets, and she bites 

 it open to allow the young to emerge, when they get upon her body, 

 and about a day afterward she drops the cocoon. Sometimes, as 

 the above list of cases shows, the mother drops the cocoon before it 

 hatches ; in all such cases this appears to be due to the mother biting 

 open the cocoon prematurely, and true to her instinct she drops the 

 cocoon after opening it ; when the cocoon is opened too early, the ova 

 do not develop further. The mother is very tenacious of the cocoon. 

 I have seized a cocoon, when attached to the mother, with forceps 

 and shaken it, with the mother, violently in the air, without dislodging 

 her hold upon it; there is, in the case of older cocoons, a very hard and 

 thick thread attaching them to the spinnerets. One mother I watched 

 when she was bending down to drink ; about half of the young upon her 

 climbed down to the water and drank of it also, but quickly returned 

 to her when she commenced to move away. In changing this mother 

 from one cage to another, a great mass of young was dislodged from her 

 back and fell upon the floor. Some of these young ran about and 

 would not return to the mother when they came in contact with her, 

 but the remainder clung together in a mass upon the floor. The 

 mother seemed excited, yet when she touched the mass of young she 

 would remain by it only a short extent of time, and did not aid the 

 young to return to her. But next day all were upon her })ack again. 

 Lyoosa verisimilis Montg. 



Parasites. — The type specimen of the female of this species was kept 

 alive some time, until she was killed by the escape of a large species 

 of Mermis. Three days preceding she dropped the large globular co- 

 6 



