VAN NAME: SIMPLE ASCIDIANS. 
489 
1891. Molgula 7iana + M. tiuda + M. littoralis Herdman, Journ. Linn. Soc. 
London, Zool., vol. 23, pp. 568, 569. 
1901. Molgula littoralis Whiteaves, Geol. Survey Canada, pub. no. 722, p. 270. 
1903. Molgula nana Hartmeyer, in Romer and Schaudinn, Fauna Arctica, 
vol. 3, p. 157. 
1906. Molgula nana Redikorzew, Trav. Soc. Nat. St. Petersbourg, vol. 37, 
pt. 1, pp. 308, 310. 
1907. Molgula citrina Alder and Hancock, British Tunicata, vol. 2, p. 62, 
pi. 26, fig. 5-9; pi. 27, fig. 6-8; pi. 28, fig. 3-5; pi. 40, fig. 4; pi. 
47, fig. 3; text-figs. 46, 47. 
1907. Molgula nana Redikorzew, Ann. Mus. Zool. Acad. Sci. St. Petersbourg, 
vol. 11, pp. 129, 132, 133. 
1908. Molgula nana Redikorzew, Trav. Soc. Nat. St. P^jtersbourg, vol. 39, 
pp. 20, 22, 42. 
1909. Caesira citrina + C. littoralis + C. nana Hartmeyer, Bronn's Tier- 
reich, vol. 3, suppl., pp. 1323, 1324. 
1912. Caesira citrina Hartmeyer, Sitzungsb. Ges. Naturforsch. Freunde, 
1912, no. 1, p. 17. 
Verrill's (1871a) description is here quoted: 
"Body transversely oblong-oval, somewhat flattened laterally, 
and attached obliquely by a part of one side (usually the right) to the 
underside of stones; when young subglobular. Integument firm and 
Text-flg. 10. — Caesira citrina (Alder and Hancock). X 4. 
tough, but translucent, the tubes similar to the body; the surface 
smoothish in young specimens, in older ones slightly wrinkled, not 
fibrous, but somewhat roughened by sparse granule-like papillae, 
to which a thin, imperfect coating of foreign substances is sometimes 
attached; in contraction the surface is reticulated with wrinkles, 
with more elevated interstices. Tubes short and stout, arising from 
the upper side, and separated by a distance about equal to or exceeding 
their diameters, quite divergent, the anal tube most so, not wholly 
retractile. The anal tube is about twice as long as the branchial and 
usually swollen in the middle, rounded at the end, with a simple square 
