COCOONING AND HATCHING OF AN ARANEAD. 



6 to 7 minutes ; in one case, 8^< minutes and in one case, where 

 the spider seemed feeble, 19 minutes. In the majority of cases 

 it lasts from 3 ^ to 4^ minutes. There is remarkable uniformity 

 in the length of duration of the act, which seems to be quite 

 independent of the number of eggs discharged. After all the 

 eggs have been extruded but while a point of the egg mass sur- 

 face still adheres to the genital aperture, the spider may continue 

 reiterated ineffectual efforts to discharge further eggs, and how 

 long it continues to do so renders the duration of the process 

 longer or shorter. 



3. Time Duration of the Spinning of the Base.- -This was 

 timed for seventeen cases, showing a variation from 14 to 37 

 minutes ; in eleven of these cases it was between 20 and 30 

 minutes. 



4. Time Duration of the Spinning of the Cover. This was ob- 

 served in thirty-two cases. In one case the process lasted 27 

 minutes ; in five cases, 40 to 49 minutes ; in eleven cases, 50 to 59 

 minutes ; in two cases, 60 to 69 minutes ; in three cases, 70 to 

 79 minutes ; in four cases, So to 89 minutes ; in three cases, 90 

 to 99 minutes ; in one case, I 10 minutes ; and in one case where 

 the spider lacked the left fourth leg, for 142 minutes. There is, 

 accordingly, considerable variation in the duration of this oper- 

 ation, due not at all to the size of the egg mass, apparently also 

 not to the rate of spinning, but rather to the thickness and firm- 

 ness of the cocoon which varies greatly. The cover making is 

 usually uninterrupted, but sometimes the spider may pause, then 

 evidently from weariness. It may be that high nourishment 

 would allow the greatest amount of silk secretion, and that in 

 well fed individuals the cocoons be largest and take the most 

 time in the making. 



5. Abnormalities in Cocooning.-- Abnormal cocoons are not 

 rare with wild individuals, and relatively more numerous with my 

 captive specimens. Generally an abnormal cocoon is due to a 

 defect in the spinning of the base ; the latter may be too small 

 or too loose, and the spider in working upon it is then liable to 

 pull it out into an irregular form. Again, the issuing egg mass 

 may by accident adhere to a leg of the spider, or even a portion 

 of it become detached from the rest ; when this happens the spider 



