1884.] Limnocodium Sowerbii, Allman and Lanhester. 11 



pieces of different size and shape upon any one filament. The smallest 

 pieces are mere knobs, and about of an inch, long ; the largest are 

 prolonged into three or four lobes, about of an inch long. , 



No tentacles are present. They may develop subsequently. The 

 basal portion tends slightly to spread over its area of attachment, this 

 portion half encircling a root-filament. 



There is no trace of a true perisarc, but the surface is covered with 

 particles of mud and other debris, which become glued together by 

 some secretion of the animal, and form a sort of tubular casing. In 

 some specimens which I have mounted I have observed this casing 

 slipping off, owing to shrinkage of the animal. 



The tip of a lobe usually projects beyond this tube, but sometimes 

 in specimens placed in cold water it withdraws itself sluggishly into 

 the tube. 



The organism does not exhibit any active movement, but upon irri- 

 tation there is a slight contraction, such as described above, and 

 accompanying this there may be an expulsion of fluid and minute 

 particles from the extremity of each lobe, demonstrating the existence 

 of an aperture to each, which presumably serves as a mouth. 



The animal throws off nematocysts when irritated. 



Preparations of the stained animal mounted whole and serial sec- 

 tions have revealed further points in its structure. 



The ectoderm cells are fairly uniform throughout, and present 

 numerous nematocysts. 



The endoderm cells are much modified in the " mouth " region, i.e., 

 at the apex of each lobe, being set very closely together, and staining 

 very deeply with carmine. 



In preserved specimens there is only a very minute lumen, leading 

 from the terminal aperture. 



Lower down the endoderm cells have a clear swollen appearance, 

 and almost fill up the enteric cavity. In the basal region the endo- 

 derm cells are normal, and the cavity is well developed, and may 

 contain particles. The peculiar arrangement of endoderm cells near 

 the apex may have no special significance, but it somewhat suggests in 

 appearance the rudiment of a sub-umbrella found in such forms as 

 Hydroctinia, Podocoryne, and Hippopodius, figured by Ed. Van Beneden, 

 and more recently by Weissmann.* 



Structures resembling Buds produced by the Medusiform Persons. 



During the summer of 1883 I discovered both in water taken direct 

 from the tank at the Botanic Gardens and in jars in which the # 

 Medusae had been kept alive for some time, minute vesicles consisting* 

 of ectodermic and endodermic layers, surrounding a closed central 

 * Die Entstehung der Sexualzellen bei den Hydrorneclusen. 



