CATALOGUE OP TUNICATA. 



Luciae of which the last is not represented in the 

 collection. 



Sub order I. ASCIDI^E SIMPLICES, Savigny, 1816. 



This group contains fixed (rarely unattached, but never 

 free - swimming) Ascidians which are solitary, and very 

 rarely reproduce by gemmation ; if colonies are formed, the 

 members of the colony are not buried in a common investing 

 mass, but each has a distinct test of its own, and gemmation 

 is not directly from the body of the parent, but from a basal 

 stolon. 



The Ascidiae Simplices include four families the Clave- 

 linida?, the Ascidiidae, the Cyntkiidae, and the Molgulidse all 

 of which are represented in the collection. 



Family I. CLAVELINIMJ, Forbes, 1853. 



Body attached by the posterior end, and usually by means of a 

 peduncle, to a creeping basal stolon or common stolonial mass, from 

 which young Ascidiozooids are formed by gemmation. 



Test gelatinous, rarely cartilaginous, usually thin and transparent. 

 Apertures circular, very rarely distinctly lobed. 



Branchial sac not folded, often without internal longitudinal bars. 

 The bars, if present, have no papillae. The stigmata are straight. 



Dorsal lamina represented by languets. 



Tentacles simple, filiform. 



Alimentary canal usually extending beyond the branchial sac poste- 

 riorly to form an abdomen. 



Gonads placed in the intestinal loop. In addition to sexual reproduc- 

 tion, colonies may be formed asexually by gemmation from the stolon. 



This family contains about 10 genera, and over 30 species. These 

 are probably the most primitive of the Ascidians. They link on in the 

 one direction through Ecteinascidia to Ciona and the Ascidiidae, and so 

 to the rest of the Simple Ascidians, and in the other direction through 

 Diazona to the Polyclinidse and other typical Compound Ascidians. 



