HYDRA 







sM 



Fig. 



-//j'dr 



I'll... 73. — iiyara. 

 [^ A, two living specimens of ll.z'iridis attached lo a bit of weed. The larger 

 specimen is fully expanded, and shows the elongated body ending distally in the 

 hypostome (/!>'^), =.urrounded by tentacles (/), and three buds (/y/.I, /'(/.-, (^(/.■l) in 

 different stages of development ; a small water-flea (^r) has been captured by one 

 tentacle. The smaller specimen (to the right and above) is in a state of complete 

 retraction, the tentacles {t) appearing like papilla;, 

 r t!, /'l./i(sca, showing the mouth {112th) at the end of the hypostome (/ly/), the 

 circlet of tentacles (/), two spermaries (j-^j'), and an ovary (oT'y) 

 C, a Hydra creeping on a flat surface by looping movements. 



I) a specimen crawling on its tentacles. (From Parker's Bioli->(^y : C and D after 

 W. Marshall.) 



hvpostome {hyp), at the apex of \Yhich is a circular aperture, 

 the mouth {mth). At the junction of the hypostome with 

 the body proper are given off from six to eight long deUcate 



