130 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



Family CLAVELINIDAE Forbes, 1848. 



[=CLAVELINIDAE+POLYCITORIDAE s. DISTOMIDAE Authors.! 



The propriety of unking these closely allied families has already 

 been suggested by several writers, including Hartmeyer, though he 

 failed to adopt the plan in his classification. 



The group thus enlarged comprises compound ascidians forming 

 colonies either of the social type with separate zooids connected by 

 stolons, or having the zooids completely buried in a common mass of 

 test and discharging into common cloacal cavities, or exhibiting any 

 of various intermediate types. Zooids without any trace of internal 

 longitudinal vessels. 



Genus CLAVELINA Savigny, 1816. 



[=Clavclina Savigny, 1816+ PodoclaveUa Herdman, 1800+Cho7idrostachys Mac- 

 Dontild, 1858+Bhodozona Van Name, 1902.] 



These genera are united on the ground that the characters dis- 

 tinguishing them are entirely superficial ones (chiefly the degree of 

 separation of the zooids in the colony), which are variable not only 

 in different colonies of one species but often in the same colony at 

 different stages of growth. 



CLAVELINA MOLLUCCENSIS (Sluiter), 1895. 



1S95. PodoclaveUa meridionalis Sluiter, Denschr. Med.-Nat. Ges. Jena, 



vol. 8. p. 1G5. pi. 6, figs. 1-4. 

 1899. PodoclaveUa meridionalis (part) Herdman, Cat. Australian Mus., 



Sydney, No. 17, pp. 5 and 112. 

 1904. PodoclaveUa molluccensis Sluiter. »S7*>o'/a-Exped., vol. 56«, p. 5. 



1908. PodoclaveUa meridionalis Pizon, Rev. Suisse Zoologique, vol. 10, p. 



197, pi. 9, figs. 1-4. 



1909. PodoclaveUa moluccensis Hartmeyer, Bronn's Tier-reich, vol. 3, 



suppl., p. 1426. 



If the writer is correct in referring all the colonies listed below to 

 this species, it is a very variable one, its characters being greatly influ- 

 enced by the age or stage of development of the colony and perhaps 

 also by the conditions under which it grows. Each zooid may have 

 its oAvn separate sheath of test inclosing the body for its entire 

 length, or only the anterior parts of the zooids may be separately 

 ensheathed, their posterior parts being embedded in a mass of test 

 common to several or all of them. In the best-developed and most 

 fully adult specimens in the collection, however, each zooid is 

 inclosed in a separate club-shaped sheath of transparent pale yellow- 

 ish gray or nearly colorless test, which becomes tough and horny on 

 the basal part of the zooid, where it is extended into a pedicel, the 

 several zooids constituting the specimen being connected only by a 



