ON BUDDING IN POLYZOA. 527 



Ectoprocta — Phylactolsemata. 

 I have treated of these later on. 



Other Authors' Observations on Adult Gemmation. 

 Entoprocta. 



According to Prof. Carl Vogt, in Loxosoma phascoloso- 

 m a turn (6), the bud is formed by a rising of the outer cellular 

 layer of the parent, carrying its cuticle along with it. The cavity 

 thus produced is filled not with '^cells'' but with an undivided 

 sarcodic mass, which very soon breaks up into homogeneous 

 non-nucleated masses of protoplasm. This anomalous material 

 at first groups itself into three masses, superiorly the hood 

 (capuchon) or lophophore, which from the first possesses a 

 central cavity, the vestibule; below this is a small solid mass of 

 cells, the stomach, and inferiorly lies the pedal gland. Other 

 differentiations of these protoplasmic masses produce the tran- 

 sitory pedal body between the stomach and pedal gland, the 

 reproductive organs between the lophophore and stomach, and 

 the general parenchyma of the body. The stomach acquires 

 a central lumen and the intestine and rectum now make their 

 appearance, also, by him, derived from the protoplasmic mass. 

 They, too, are at first solid. The oesophagus is a diverticulum 

 from the hood. The tentacles are the last organs to make 

 their appearance, then the vestibule first opens to the outer 

 world, and the rectum into it, and the bud becomes detached. 

 In this form the pedal gland atrophies. The author informs 

 us that he has tried the effect of various reagents and also 

 section-cutting, but has " abandoned these methods, which de- 

 mand so much time and care, and in the present case could 

 give me no positive information upon points which direct 

 observation of the living organism had failed to solve." It 

 appears to me that the formative elements of the bud are true 

 cells, as all other observers maintain, and that the earliest 

 stages were incorrectly determined. The difficulties of the 

 homologies of the parts vanish, if taking a somewhat later 

 stage, we look upon the anterior mass with its central hollow 



