THE CAMPANULAEID^ AND THE BONNEVIELLID^. 



27 



Campanularia Integra and Orthopyxis caliculata have the most extensive geographical dis- 

 tribution of all the American Campanularidse, each being found in 14 of the 17 regions embraced 

 in the table. It may be of interest to note that both of these have remarkably thickened 

 hydro thecse and both are comparatively shallow-water forms. 



Doubtless the habit of growmg on floating timbers, seaweed, etc., which characterizes so 

 many campanularians will account, in some measure at least, for the' wide distribution of many 

 species, and the profusion of free-swimming medusae produced by Obelia and some other genera 

 is another factor leading to the same result. 



Bathymetric distribution. — In comparing this table with the corresponding ones for the 

 Plumularidse (part 1, p. 501) 'and the Sertularidse (part 2, p. 45), it at once appears that there 

 are relatively many more shallow-water species in the Campanularidse than in either of the 

 other families thus far treated in this work. 



It should be explained that in the table giving the bathymetric distribution of the Cam- 

 panularidse there are very many between-tide and shaUow-water forms for which no data 

 regarding depth can be found. In such cases the depth is given arbitrarily as "1-10 fath.," 

 and in none of these cases has a depth greater than 10 fathoms been recorded, the context 

 indicating that the species are found on seaweed or along the shores and have not been secured 

 by dredging. 



Thirty-eight species (or 49 per cent) of all American Campanularidffi are reported from 

 depths not greater than 10 fathoms, while 57 (or 72 per cent) have not been reported from 

 depths greater than 50 fathoms. Seventy-four of the 81 species have been found at a depth 

 of less than 50 fathoms. 



Adding to the table on page 49, part 2 of this work, the corresponding data concerning the 

 C amp anul arid se, we have the following comparison of the bathymetric distribution of the 

 Plumularidse, Sertularidee, and Campanularidffi: 



Comparative distribution at increasing depths. 



Family. 



Less than 

 50 fathoms. 



Over 60 

 fathoms. 



Over 100 

 fathoms. 



Over 150 

 fathoms. 



Over 200 

 fathoms. 



Over 500 

 fathoms. 



Over 1,000 

 fathoms. 





Per cent. 

 50 

 75 

 94 



Per cent. 

 63 

 40 

 23 



Per cent. 

 49 

 30 

 19 



Per cent. 

 40 

 26 

 9 



Per cent. 

 28 



16 

 6 



Per cent. 

 5 

 6 

 



Per cent. 

 3 

 3 

 









This table shows at a glance that the Campanularidse are relatively shaUow-water forms 

 as compared with the Plumularidse and SertularidEe. 



The deepest haul which has 3delded an American campanulaiian was at Albatross station 

 2415, lat. 30° 44' N.; long. 79° 26' W., where Campanularia marginata was found and a depth 

 of 440 fathoms was reported. Campanularia macroscypha was found by the Bureau of Fisheries 

 steamer Albatross at station 2664, lat. 29° 41' N.; long. 79° 55' W. at a depth of 373 fathoms, 

 and Campanularia verticillata has been reported by Bonnevie from off the Norwegian coast 

 at a depth of 328 fathoms. 



Outside of the genus Campanularia, none of the Campanularidse has been reported from a 

 greater depth than 110 fathoms {Gonothyrsea gracilis). Clytia joTinstoni and Eucopella cali- 

 culata have been reported from 100 fathoms. The deepest known habitat for an Obelia is 80 

 fathoms, where 0. longissima has been found, while no member of the genus Silicularia has 

 been reported from a greater depth than 10 fathoms. 



Genus CAMPANULARIA Lamarck (modified by Hincks). 



Trophosome. — Colony branched or unbranched. Hydrothecse usually strictly campanulate. 



Gonosome. — Gonangia containing fixed sporosacs from which planulse are directly developed. 



Lamarck gives the following definition : ' 



Polypier phytoi'de fiLiforme, sarmenteux, come; a tiges fistuleuses, simples ou rameuses. 



Calyces campanules, denies sur les bords, soutenus par des pedoncules longs et tortilles. 



• Histoire Nat. Anim. sans Vert., vol. 2, 1836, p. 129. 



