502 ANATOMICAL AND PATHOLOGICAL OBSERVATIONS. 



membranes composing the sac. Generated by means of cells 

 arising from a germinal membrane. Internal cavity filled with 

 a watery fluid. 



1.^ — Aceinlialocystis simplex {Mihi). 



Parent sac quite transparent, with the membranes indivisible and the 

 germinal cells very mmute. 



2. — Acephalocystis monroii {Mild). 



Parent sac transparent and gelatinoiLS ; germinal membrane intersected by 

 membranous bands, which form flattened compartments, in which are large 

 cells containing unequal numbers of young cells. Each of the young is • 

 marked with one or more dark spots. 



3. — Acephalocystis armatus {Mihi). 



Parent sac opaque, membranes distinct, germinal membrane composed of 

 a soft granular matter, in which the germs are arranged irregularly ; they are 

 globidar and armed with an irregular circlet of teeth at the part opposite that 

 of attachment. 



IL ASTOMA (mihi). 



Not buried, but attached by means of a pedicle, which 

 becomes very slender as the animal increases in size. Young, 

 globular and corrugated ; adult, botryoidal and smooth ; epithe- 

 lial cells ; with some appearance of tubuli in external coat. 

 Young remain and increase in size within the membranes of the 

 parent, till she bursts, when they become attached to the 

 peritoneum. 



4. — Astoma acepthalocystis {Mihi). 



Botryoidal, that part of the interior not occupied with the young fiUed 

 with a yellowish gelatinous matter. 



in. DISKOSTOMA (mIHI). 



Peduncular. Whole group covered by a disk bearing 

 tubular membrane. 



5. — JDisJcostoma acephalocystis {Mihi). 



Globular interior filled with gelatinous matter, of a transparent greenish 

 ellow colour. 



