108 The Structure and Habits of Spiders. 



under which is a pair of little knobs, such as ap- 

 peared at first on the thoracic segments ; then 

 appear two pairs, then three, and so on, till there 

 are six pairs, which mark the six segments of 

 the abdomen. Up to this time, the embryo has 



Fig. 64. 



been rolled up with the under side outward ; but 

 now it begins to turn, and in a day or two has 

 its back outward, Fig. 64, c. The constriction 

 between the thorax and abdomen begins about 

 this time ; and in a few days more the spider is 

 ready to hatch, Fig. 64, d. 



