VAN NAME: SIMPLE ASCIDIANS. 569 
examined by Kiaer and identified with his species. This form might 
almost equally well be placed in Pandocia [Polycarpa], as was done by 
Kiaer. Tcthyum joanae (Herdman), 1898, and T. stimpso7ii (Ritter), 
1900, are closely allied forms from Puget Sound. 
Tethyum plicatum (Lesueur). 
PI. 62, figs. 104, 105; PI. 63, fig. 108; PI. 68, fig. 136; text-fig. 36. 
1823. Ascidia plicata Lesueur, Journ. Acad. Nat. Sci. Philadelphia, vol. 3, 
p. 5, pi. 3, fig. b. 
1843. Ascidea plicata DeKay, Zool. New York, Mollusca, p. 259. 
1877. Styela gyrosa Heller, Sitzungsb. Akad. Wiss. Wien, vol. 37, p. 255, 
pi. 3, fig. 7-12; pi. 4, fig. 1-8. 
1883. Styela plicata Traustedt, Vidensk. Meddel. Naturhist. For. Kjobenhavn 
for 1882, p. 123, pi. 5, figs. 6, 16. 
1883. Styela plicata Traustedt, Mitt. Zool. Stat. Neapel, vol. 4, p. 478, pi. 36, 
fig. 12. 
1891. Styela plicata Herdman, Journ. Linn. Soc. London, Zool., vol. 23, p. 581. 
1900. Styela plicata Metcalf, Zool. Jahrbucher, Anat., vol. 13, p. 516, pi. 36, 
figs. 24, 25. 
1900. Styela sp. Wilson, Amer. Naturalist, vol. 34, p. 354. 
1905. Styela plicata Hartmeyer, Zool. Jahrbucher, Suppl., vol. 8, p. 384. 
1909. Tethyum. plicatum Hartmeyer, Bronn's Tier-reich, vol. 3, suppl., 
p. 1359. 
1912. Tethyum plicatum Hartmeyer, Denkschr. K. Akad. Wiss. Wien, cl. 
math.-nat., vol. 88, p. 20. 
Apparently not Cynthia vittata Stimpson, 1852, p. 230, as that has 
"about fourteen branchial folds," and is probably one of the Pyuri- 
dae. 
The following description was made from several large specimens 
growing in a closely crowded group or cluster, which no doubt affected 
their shape. 
Body irregularly clavate, 58 mm. long, by 25 mm. wide, in the 
largest specimen, with the branchial aperture at the larger end and 
the atrial aperture a little way back on the dorsal side. Body a.ttached 
by the smaller end, or more or less obliquely by one side. Apertures 
both four-lobed on rather prominent projections. 
Test moderately thick and very tough, the surface thrown into 
coarse deep wrinkles (mainly longitudinal) and irregular prominences. 
Alcoholic specimens of a dirty brownish white color. It is said to be 
whitish in life also. 
Mantle of only moderate thickness. It contains a layer of closely 
