CTENOPHORES IN THE GULF OF MEXICO 



By Mary Sears, Woods Hole Oceanographic Institution 



Ctenophores are so fragile that they are not 

 readily preserved or, if they are, certain diagnostic 

 characters may become obscured. Thus, many 

 records of their occurrence are somewhat un- 

 certain. Equally uncertain are their names be- 

 cause about 40 years ago four important papers 

 appeared almost simultaneously (Bigelow 1912; 

 Mayer 1912; Mortensen 1912; Moser 1912), and 

 insofar as I can ascertain, nobody has reviewed 

 the group critically since that time. It is probable, 

 however, that the ctenophore fauna of the Gulf 

 of Mexico is as well known as that of any neigh- 

 boring area due to Mayer's (1900, 1912) and 

 Fewkes' (1882) observations at the Tortugas. 

 Nevertheless, only about a dozen species have been 

 recorded with any certainty in the Gulf: Beroe 

 ovata Bosc; Bolinojpsis vitrea L. Agassiz; Cestum 

 veneris LeSueur; Eurhamphaea vexilligera Gegen- 

 baur; Folio parellela Fol; Hormiphora hormiphora 

 Gegenbaur; Leucothoe ochracea ' Mayer; Mne- 

 miopsis mccradyi Mayer; Ocyropsis crystallina 

 Rang; Ocyropsis maculata Rang; Tinerfe beehleri 

 Mayer; Tinerfe lactea Mayer (using the names 

 that appear to be acceptable today). This is a 

 slight reduction in the number originally described 

 because a number proved to be identical with 

 species which had been described earlier. This 

 list also includes most of the species that have 



' Fewkes' (1882) record of Euchar.s muUicornit Quoy and Oaimard is con- 

 dered by Mayer (1912, p. 35) to have been his new species, Leucothoe ochracea. 



been reported from neighboring parts of the 

 Atlantic. Whether other species will be found 

 in this area seems problematical. At any rate, 

 although ctenophore species are more numerous 

 in the Gulf, they apparently do not occur in dense 

 swarms as is so characteristic of them in more 

 northern waters. 



LITERATURE CITED 



Bigelow, H. B. 



1912. Reports on the scientific results of the expedition 

 to the eastern Tropical Pacific . . . XXVI. The 

 ctenophores. Bull. Mus. Comp. Zool., Harvard 

 College, 54 (12): 369-404, 2 pis. 

 Fewkes, J. W. 



1882. No. 7. Explorations of the surface fauna of the 

 Gulf Stream, under the auspices of the U. S. Coast 

 Survey by Alexander Agassiz. 1. Notes on acalephs 

 from the Tortugas with a description of new genera 

 and species. Bull. Mus. Comp. Zool., Harvard 

 College, 9: 251-289, 7 pis. 

 Mayeh, a. G. 



1900. Some medusae from the Tortugas, Florida. 

 Bull. Mus. Comp. Zool., Harvard College, 37 (2): 

 13-82, 44 pis. 

 1912. Ctenophores of the Atlantic coast of North Amer- 

 ica. Carnegie Inst. Washington Pub. No. 162: 58 

 pp., 17 pis. 

 Mortensen, Th. 



1912. Ctenophora. Danish Ingol} Exped. 5 (2): 95 

 pp., 10 pis. 

 Moser, F. 



1912. Die Ctenophoren der Deutschen Sudpolar Ex- 

 pedition 1901-1903. Deutsche Sudpolar Exped. 11 

 (Zool. 3): 117-192, 1 text fig., pis. 20-22. 



297 



