CLASSIFICATION OF THE TUNICATA. 643 



Nine species of Dolioluvi are known, wbicli may be distin- 

 guished as follows : — 



(Branchial sac with only a few stigmata at its posterior end, forming 

 a straight line 1 

 Branchial sac with numerous stigmata extending along the greater 

 part of its length, and forming a curved line 2 



J f Only 5 pairs of stigmata J), varum, Grobben. (Med.) 



I At least 10 pairs of stigmata 3 



g r 10-12 pairs of stigmata JD. 3IuUeri,Ki: (Med.) 



1 26 pairs of stigmata J). Krohni, Kerdm. (S. Pac.) 



2 r Stigmata starting dorsally near the 1st muscle-band 4 



\ No stigmata reaching to tlie 1 st muscle-band dorsally 5 



{Stigmata reaching to the 1st muscle-band ventrally. [Med.) 



I>. Ehrenhcrgi, Kr. (S. Pac, AtL, 

 No stigmata in front of the 3rd muscle-band ventrally. 

 D. affine, Hordm. (Pac.) 



K f Stigmata starting dorsally about the 2nd muscle-band 6 



\ Stigmata starting dorsally behind the 3rd muscle-band 7 



{Stigmata reaching back to the 5th muscle -band. 

 B. ChaUengeri, Herdm. (Pac.) 

 Stigmata reaching back to the 6th muscle-band. [& Atl.) 



B. denticulatum, Q. & G. (S. Pac. 

 (Stigmata reaching only to the 5th muscle-band ventrally. 

 B. GegenbawiyV^. (Austr.,Med.) 

 Stigmata reaching nearly to the 4th muscle-baud ventrally. 

 B. tritonis, Herdm. (N. Atl.) 



Anchinia* (UscJiscJioltz, 1835), C. Vogt. 



Body rounded, somewliat elongated dorso-ventrally, not 

 attached, and not forming a colony. Branchial aperture anterior, 

 atrial posterior, both lobed. 



Test well developed, containing branched test-cells. 



Mantle having only 2 anterior and 2 posterior ring-like muscle- 

 bands, and an S-shaped band on each side in the middle. 



Branchial sac having only an oblique row of stigmata at its 

 posterior end. 



Alimentary canal forming a U-shaped loop. 



Gonads placed on the right side o£ the body. 



The life-history, so far as is known, is similar to that of 

 Doliolum, but the three forms of the polymorphic sexual gene- 

 ration do not occur together on one stolon or outgrowth, but are 

 produced successively. 



There is only one species known, AncJiinia rubra, ^ogt, from 

 the Mediterranean. 



* The Boliopsis of C. Vogt. 



