2 THE VOYAGE OF H.M.S. CHALLENGER. 



the North Athmtic. Heller ^ has described several new Plumularidse from the Adriatic. 

 To Professor Milieu Coughtrey," of Otago, we owe descriptions of New Zealand species, 

 and to Surgeon James Armstrong/ of the Indian Medical Department, descriptions of 

 species collected by him on the eastern shores of India. 



Besides the expedition of the Challenger, other recent exploratory expeditions have 

 largely added to our knowledge of this group. The exploration of the Gulf Stream, by 

 the United States Coast Siirvey,* has brought to light many new and beautiful forms, 

 the voyages of the " Porcupine " * have made us acquainted "ftdtli new species fi-om 

 the North Atlantic, and the explorations by the United States Coast Survey Steamer 

 " Blake " in the Carribbean Sea and alous; the Atlantic Coast of the United States have 

 brought to our knowledge the occurrence in those regions of a rich plumularian fauna, 

 among which are several new and highly interesting forms." 



To the number of species thus determined and described the collection of hydroids 

 l)rought home by the Challenger makes a large and valuable addition. Of this collection 

 the family of the Plumularidse forms a considerable proportion. Among these, four 

 species, namely, Acanthella cffusa, Acanthocladium huxleyi, Aglaojihenia macgillivrayi, 

 and Lytocarpus longicornis had been already described by Busk from the voyage of the 

 " Rattlesnake," and one, namely, Lytocarpus secundus, by Kirchenpauer, from specimens 

 brought home by Semper from the Pelew Islands. The Challenger also obtained from 

 dredgings off Bermuda a species {Aglaophenia ramosa) already described in the Eeport 

 on the Hydroida of the United States exploration of the Gulf Stream. 



The only form which can be identified with a species occurring in the European seas 

 is Cladocarpus formosus. This species was dredged by the " Porcupine " from the seas 

 lying to the north of Scotland, and by the Challenger from the seas of Japan. The species 

 is a well-marked one, and the gTeat distance between the Atlantic and Pacific stations 

 without any intermediate station having been discovered, is a remarkable and signifi- 

 cant fact. 



But by far the greater part of the Plumularidaj brought home by the Challenger consists 

 of species new to science, while among these a considerable number must be assigned to 



1 Prof. C. Heller, Die Zooi^hyten und Echinodermen des adriatisclieu Meeres, Wien, 1868. 



- Millen Coughtrey, Notes on the New Zealand Hyrdoida. Journal of the New Zealand Institute, vol. vii. 

 1874. 



* Description of some new species of Hydroid Zoophytes from the Indian Coasts and Seas, by Siu'geon James 

 Armstrong, Marine Survey Department. Journal of the Asmtic Society of Bengal, vol. xlviii., 1879. 



* Geo. J. Allman, Keport on the Hydroida collected during the exploration of the Gulf Stream, Ijy L. F. De 

 Pourtales, United States Coast Survey. Mem. of Mus. Comp. Zool. at Harvard Colleye, vol. v., No. 2, 1877. 



° Geo. J. AUman, Eeport on the Hydroida collected during the expeditions of H.M.S. "Porcupine." Trails. Zool. 

 Soc. Land., 1873. 



° Reports on the results of dredging under the supervision of Alexander Agassiz in the Caribbean Sea in 1878-79, 

 and along the Atlantic Coast of the United States during the summer of 1880, by the U.S. Coast .Survey Steamer 

 " Blake," Commander J. E. Bartlett, U.S.N., commanding. Eeport on the Acalephse by J. Walter Fewkes. Bull. Mus. 

 Comp. Zool. at Harvard College, vol. viii. p. 127. 



