CATALOGUE OF TUNICATA. 93 



L. pustulosum, Sluiter, Amboina. 



L. torresii, Sluiter, Thursday Is. 



L. sipkoniatum, Sluiter, Amboina. 



L. asteropum, Sluiter, Amboina. 



There are no Diplosomidae in the collection, and the only one known 

 from Australian seas is : 



Family IV. DIPLOSOMID-ffi. 



Diplosoma Bayneri, Macd., Sydney.] 



Section B. HOLOSOMATA, Sluiter,* 1895 (restricted 



Herdm., 1898). 



Compound Ascidians, in which the body is sht.rt and 

 compact, the alimentary and reproductive viscera being 

 alongside the branchial sac. There are two families. 



Family I. POLYSTYELID^l, Herdman, 1886. 



Colony massive or encrusting, sessile, rarely pedunculated, or formed 

 of small masses connected by stolons. No common cloacal cavities 

 present. 



Ascidiozooids large, and usually short-bodied, rarely with a distinct 

 abdomen. Both apertures 4-lobed, and opening directly to the exterior. 



Test firm and cartilaginous. Matrix generally fibrillated, test cells 

 small and inconspicuous, bladder cells rarely or never present. Vessels 

 abundant, branched, and provided with distinct terminal bulbs. 



Branchial sac large and well-developed. Folds sometimes present. 

 Internal longitudinal bars strong and fairly numerous. 



Dorsal lamina in the form of a plain membrane. 



Tentacles numerous, simple. 



Alimentary canal usually placed alongside the branchial sac, rarely 

 extending beyond it posteriorly. 



Gonads in the form of polycarps, attached to or imbedded in the 

 mantle, and projecting into the peribranchial cavity. 



Gemmation effected by means of out-growths from the mantle, which 

 later become connected with the vascular prolongations from the Ascidio- 

 zooids into the common test. 



* I use Skater's term in the restricted sense as defined above. Sluiter would include 

 also the Simple Ascidians. 



