774 



CHARLES L. BOULENGEK. 



In Moerisia 1 yon si the medusa-buds are to be found 

 scattered irregularly on the broadest region of the hydranth 

 between the bases of the tentacles (Text-fig. 4), thus differing 

 in position from the asexual lateral buds, which are restricted 

 in the majority of cases to the more proximal parts of the 

 body. 



Text-fig. 4. 



m 



tent. 



Outline sketcli of a hydi-anth of Mcerisia lyonsi to show 

 developing ^onopliores and a small asexual bud. X6^J. tenz. 

 Tentacle, m.b. Gonophore Tvith conspicuous ocellar biUbs. 

 as.b. Asexual lateral bud. 



The ectoderm of this region is somewhat deeper than m 

 other parts of the hydroid, the boundaries of the large 

 musculo-epithelial cells are difficult to detect, and the whole 

 tissue is crowded with interstitial cells, for the most part 

 nematoblasts, containing nematocysts in various stages of 

 development. The endoderm consists of large vacuolated 



