W. G. YanName — Bermuda Ascidlans. 833 



Before proceeding to the description of the species, I wish to 

 express n\v thanks to Prof. A. E. Verrill for tlie use of liis material 

 and for much vaUiable advice and assistance. I am also indebted 

 to Prof. II. C. Bumpus and Prof. H. M. Smith, of the United States 

 Fish Commission, for the opportunity of working at the Fish Com- 

 mission laboratory at Wood's Hole, where a portion of this work was 

 done, and also to Prof. S. I. Smith and Dr. W. R. Coe of Yale 

 University, and Mr. T. Goodwin Gosling of Hamilton, Bermuda. 



WiLLARD G. Van Name. 



New Haven, Conn., December, lOol. 



Descriptions^ of Species. 

 ASCIDIiE COMPOSlTiE. 



Fixed ascidians which reproduce by gemmation, forming colonies 

 the individuals of which remain united together by stolons or by 

 being more or less completely buried in the common test. This 

 group is usiially regarded as a sub-order. 



Family CLAVELINIDiE Forbes, 1853. 



Body attached by the posterior end or more or less entirely buried 

 in a creeping basal stolon or common stolonial mass, from which the 

 3'oung zooids form by gemmation. Test usually gelatinous, aper- 

 tures simple, or (rarely) lobed. 



Branchial sac not folded, with or without longitudinal bars. 



Dorsal lamina represented by or provided with languets. 



Alimentar}^ canal extending beyond the thorax to form a distinct 

 abdomen. 



Reproductive organs in or beside the intestinal loop. 



GeuTis Claveiina Savigny, 1816. 



Zooids oblong or club-shaped, nearly independent, each enveloped 

 in its own test and connected by stolons arising from the posterior 

 end. 



Apertures not lobed. Mantle muscles mainly longitudinal. 



Branchial sac with straight stigmata, with no internal longitudinal 

 bars or papillae, but with horizontal membranes. 



The Bermuda species of this genus belongs in Herdraan's sub- 

 genus Stereocldrella, which differs from the tj^pical Claveiina in 

 having the stolons united in a basal thickening or mass of test. 



