640 INVERTEBRATE MORPHOLOGY. 



3. Suborder Pyrosomidce. Colonial forms, the various in- 

 dividuals imbedded in a common test, and opening into 

 a common cloaca ; pelagic ; with alternation of genera- 

 tions. Pyrosoma. 



3. Order Thaliacea. Simple pelagic forms, with alternation of 

 generations. Salpa, Doliolum, Octacnemus. 



LITERATURE. 



HEMICHOKDA. 



W. C. Mclntosh. Report on Cephalodiscus dodecalophus, Mclntosh, a New 

 Type of the Polyzoa. Scieut. Results of the Voyage of H.M.S. Chal- 

 leuger, xx, 1887. 



S. F. Harmer. Appendix to Report on CepJialodiscus. Scient. Results of the 

 Voyage of H.M.S. Challenger, xx, 187. 



E. R. Lankester. A Contribution to the Knowledge of Rhabdopleura. Quar- 

 terly Jouru. Microscop Science, xxiv, 1884. 



G. H. Fowler. The Morphology of Rhabdopleura Normanni Allm. Festschrift 

 fiir R. Leuckart. Leipzig, 1892. 



A. Agassiz. The History of Balanoglossus and Tornaria. Memoirs American 



Acad. Arts aud Sci., ix, 1893. 

 W. Bateson. The Early Stages in the Development of Balanoglossus (sp. incert.). 



Quarterly Journ. Microscop. Science, xxiv, 1884. 

 The Later Stages in the Development of Balanoglossus Kowalewskii, 



with a Suggestion on the Affinities of the Enteropneusta. Quarterly Journ. 



Microscop. Science, xxv, Suppl., 1885 ; xxvi, 1886. 

 - The Ancestry of the Chordata. Quarterly Jouru. Microscop. Science, 



xxvi, 1886. 



T. H. Morgan. The Growth and Metamorphosis of Tornaria. Journ. of Mor- 

 phology, v, 1891. 

 J. W. Spengel. Die Eateropneusten. Fauna und Flora des Golfes von Neapel. 



Monogr., xvm, 1893. 

 T. H. Morgan. The Development of Balanoglossus. Jouru. of Morphology, 



ix, 1894. 



CEPHALOCHORDA. 



W. Rolph. Untersuchungen fiber den Bau des Amphioxus lanceolatus. Mor. 

 phologisches Jahrbuch, 1876. 



B. Hatschek. Studien fiber Entwickluny des Amphioxus. Arbeiten aus d. 



Zool. Inst. Wieu, iv, 1881. 



E. Ray Lankester. Contributions to the Knowledge of Amphioxus lanceolatus, 



Yarrell. Quarterly Journ. Microscop. Science, xxix, 1889. 

 B. Lwoff. Ueber Bau und Entwickluny der Chorda von Amphioxus. Mitth. a. 



d. Zoolog. Station /u Neapel, ix, 1889. 

 E R. Lankester and A. Willey. The Development of the Atrial Chamber of 



Amphioxus. Quarterly Jouru. Microscop. Science, xxxi, 1890. 



F. E. Weiss. Excretory Tubules in Amphioxus lanceolatus. Quarterly Journ. 



Microscop. Science, xxxi, 1890. 



