Gatenby. — Life-history and Habits of Migas distinctus. 237 



Life-history. 



About the months of February and March the female lays from thirty 

 to sixty small white eggs. These are placed between the wall of the nest 

 and a piece of silk stretched across a rounded part of the tube (fig. 10, O t 

 the arrow). 



The egg-bag is placed variously in the nest, but in fig. 14 (top) 

 the commonest position is shown. The piece which stretches across the 

 sides of the tube is fin. in diameter. Separate egg-cases, with two sides, 

 not connected to the tube, are rare. The young emerge and lie dormant 

 inside the case. After a week or so the mother removes the covering, 

 and often weaves in lieu of it a transparent filament-like veil of silk- 

 over them (fig. 10, b). 



After the young become strong enough they push out of the covering,, 

 and wander out of their old home. Often some few remain with their 

 mother, and frequently are met with as late as the end of April. These 

 must be provided with food by their parent, for they are often a fair size- 

 When the young emerge from the parent nest the majority are pounced 

 upon and eaten by an eager, hungry horde of bank-inhabiting, vagabond 

 spiders. Few escape; those that do proceed to burrow their tiny tunnels 

 and to make their nests. They bite out the earth with their falces, which 

 are very strong. Of course, the state of the earth determines the length 

 of time taken to make the boring. The doors of the nests of young 

 spiders are round, very small, being less than T V in. in diameter, ami 

 very difficult to detect. As the spider grows she needs to enlarge her door- 



Enlargement of Tube and Door. 



If the food-supply is good the spider grows rapidly, and soon the 

 nest becomes too small for her. When she wishes to enlarge her nest she 

 tears away one side of the silken lining of the nest and widens that side 

 in its entire length. She then spins a silk web over this. The door is 

 enlarged as shown in fig 7, a, b, c, d, e. Fig. 7, a, shows a door which has 

 been enlarged once, the original door of the young spider being the circle 

 inside the larger door. Fig. 7, e, shows a door which has been enlarged 

 six times. Nests are seen with nine or ten enlargements. 



When the spider wishes to enlarge her door, after having enlarged the 

 tube, she spins under the old door an entire silk layer the size of the 

 newly enlarged tube. The door after a few enlargements becomes very 

 ragged, and hence less conspicuous. The newly spun layer is covered with 

 earth where the edge protrudes beyond the rim of the old door. Where 

 the lids have a thick earthy layer, and only one or two silken ones, the 

 spider cements a rim of earth around the old door and then spins a web 

 underneath it. I believe the spider enlarges her door and tube six or 

 seven times during her life. 



The Spider's Enemies, etc. 



Although encased in a strong tube with a deceptive door, this Arachnid 

 is not free from enemies. The greatest destroyer is excessive heat. In 

 the middle of summer the banks, especially the clay ones, become very 

 liot. Unless the spider is able to capture enough juicy insects to assuage 

 her thirst she soon becomes dusty and emaciated, and ultimately suc- 

 cumbs. Sometimes before she dies, in a last despairing effort to evade 

 the ardent rays of the sun, she weaves a silken partition between herself 



