REPORT ON THE TUNICATA. 



99 



first described it in 1831. Two years later (1860) Claparede 'likewise observed this 

 remarkable condition of the test in specimens obtained on the west coast of Scotland.^ 



In 1871 two short papers appeared, Notes on Appendicularia, by Saville Kent,' 

 and On the anatomy of the genus Appendicularia, by E. Moss,'' the latter containing 

 the description of a new species with a remarkable branchial sac resembling that of 

 the genus Doliolnm. 



AVe now come to the most important paper which has been written on the 

 Larvacea — the only one which shows any approach to being a monograph of the group. 

 It is Fol's Etudes sur les Appendiculaires du dctroit de Messine,* published at Geneva 

 in 1872. This work contains a detailed account of the anatomy and histology of the 

 family, followed by a full description of the genera and species, illustrated by eleven 

 admirable plates and some woodcuts. Fol divides the family Appendiculariidae as 

 follows : — 



' Body compact, cndostyle straight, tail 

 tliree to four and a half times the 

 length of the body. No hood. 



OAvpkura. 



/ Having a heart, an endostyle with 

 ciliated bands, and a shorter or ^ 

 longer intestine between the stomach 

 and the rectum. 



Appendiculariid^. 



Body elongated, endostyle curved, tail 

 one and a half times the length 

 of the body. A fold of the integu- 

 ment forms a hood. Fritillaria. 



Having no heart nor endostyle. The 

 pharynx is provided with four rows 

 of ciliated processes. No intestine 

 \ except the rectum. 



Koicalcvskia. 



He describes altogether eleven species ; five belonging to Oikoplcura, five to 

 Fritillaria, and one to Koivalevskia. In a further paper in 1874,'' Fol adds a new 

 genus to the group under the old name ApixncUcularia. 



In the same year Ray Lankester ' gave an account of the interesting structure of the 

 heart in a species which he investigated at Naples. The walls of this organ are formed 

 of two cells only which occupy its ends, and are connected by very delicate contractile 

 fibrils of protoplasm. 



A couple of short papers by A. Sanders' appeared also in 1874, dealing with some 

 points in the structure of some Appeudiculariida) which appeared in great abundance 



' ZeitscJir.f. wiss. ZooL, Bd. s. p. 405. 



- It is curious that all the records of the occurrence of Appcndicularians with the " Haus "' attached couie from 

 northern seas. Jlerteus' original specimens were from Berhig Strait, Allmau's and Claparede's from the Scottisli 

 coasts, and Prof. M'Intosh has recently informed me that specimens with the " H.aus " occurred in abundance in St. 

 Andrews Bay during 1887 (see also Ami. and Mai/. Nat. lii.'it., ser. .5, vol. xx., p. 102). 



2 Quart. Joitrn. Mia: S'ci., N.S., vol. xi. p. 267. •• Trans. Linn. Soc. Limd, vol. xxvii. p. 299. 



^ Man. ,Soc. (It Phijs. et iVHist. Nat. ilc Genh-c, tom. xxi. 



'' Archii-es tie Zool. exper., tom. iii. p. xlix. ' Quart. Journ. Micr. .Sci., N.S., vol. xiv. p. 274. 



* Monlhhj Micr. Journ., vol. xi. p. 141 ; and vol. xii. p. 209. 



