COCOONING AND HATCHING OF AN ARANEAD. 3 



presses her genital aperture against the concavity of the base ; a 

 yellow drop of fluid pours out and immediately adheres to the 

 concavity of the base, the eggs rapidly flowing out into it until 

 the whole reaches a size quite equal to that of the spider's abdo- 

 men. The spider touches the surface of the egg mass only with 

 the lower surface of her abdomen ; during the oviposition there 

 are repeated pressures of the abdomen against the egg mass. 

 The yellow fluid is at first of thin consistency and soon dries 

 upon the eggs ; but in drying it does not glue them together. 

 Shortly after the discharge of all the ripe eggs the spider by a 

 few quick contractions detaches her epigynum from the surface 

 of the egg mass, and immediately starts to make the cover of 

 the cocoon, spinning first upon the exposed surface of the egg 

 mass until the latter is covered, then upon the surface of the base 

 also. From her spinnerets she draws out a continuous, com- 

 pound thread with the fourth legs used alternately, applying this 

 thread to the growing cocoon, while at the same time rotating 

 the cocoon slowly with the third pair of legs (with the occasional 

 help of the second), the spider still hanging to the web above 

 the cocoon by the first pair. Thus the eggs become quickly 

 hidden from sight, by the making of a closely knit cover com- 

 posed of one continuous thread. Throughout the whole opera- 

 tion the spider keeps pressing the tips of her palpi against the 

 cocoon, which gives her a knowledge of the progress of the 

 progress of the work ; there can be no question that she is 

 guided entirely by the sense of touch, for during her labor she 

 is is so placed as to be unable to see the cocoon. Towards the 

 close of the cover making she spins closer, with the result that 

 the exterior surface of the cocoon has the firmest texture. The 

 spinning finished, she feels over the entire surface with her palpi. 

 Rarely does she leave the cocoon hung upon the suspensory 

 thread, usually she carries it higher up into the web and attaches 

 it to the object that roofs the latter. 



The finished cocoon varies from yellowish to dark brown in 

 color, and large ones may reach a diameter of 10 mm. It is 

 quite smooth externally, pyriform and usually pointed at the 

 upper end where the suspensory thread was first attached. 



More than two hundred cocoons were produced by my spiders, 



