Boone, Coelenterata, Cruises of "Eagle" and "Am," 1921-28 49 



three-sided, furrowed pit projecting inward from the surface of the 

 exumbrella. There are about sixteen marginal lappets between each 

 pair of rhopalia, the velar lappets having rounded margins, while the 

 ocular lappets are longer and sharp pointed. 



The manubrium is thick, rigid, extending 30 to 50 mm. below the 

 bell, composed of the laterally coalesced eight radial arms, which are 

 free only at the distal end, these free ends bifurcating and flaring 

 outward at the lower end of the manubrium. Each of the eight arms 

 has a deep groove on its lower side; this groove branches twice and 

 extends over the free ends of the arms. The free edges of this branch- 

 ing groove are in turn much branched and folded and possess a row 

 of many small, knobbed tentacles, constantly in motion to drive food 

 particles into the mouth-groove. There are sixteen blade-shaped 

 scapulets attached to the upper part of and occupying more than half 

 the length of the manubrium. These bear many slit-like lateral 

 mouths, the free edges of which are much crenulated and furnished 

 with small tentacles of the same type found in the free margin of the 

 central mouth. The eight principal mouth-grooves of the manubrium 

 lead into a four-cornered central aesophagus, which opens into the 

 wide, lenticular stomach, situated in the middle of the umbrella. 

 There are sixteen branches, four from each side of the aesophagus, 

 that extend outward to the slit-like mouths of the scapulets. From 

 the stomach sixteen radial canals extend outward, the outer half of 

 each canal branching many times and terminating in fine anastomos- 

 ing branchlets which establish communication among all the radial 

 canals. There is no ring canal present. The gonads are located in 

 the four folded regions of the wall of the subumbrella at the base 

 of the deep, cylindrical subgenital pits. Both the circular muscle 

 areas and the radial muscle areas are well developed. 



References: Cephea rhizostoma Gibbes, Fauna of South Carolina, 

 p. xxiii, 1847. Published as an appendix to Rept. Geology of South 

 Carolina, by M. Tourney, state geologist, Columbia, S. C. 



Stomolophus meleagris Agassiz, L., Contrib. Nat. Hist. U. S., vol. Ill, 

 pi. 14, figs. 1-8, 1860 ; ibid, vol. IV, pp. 138, 151, 1862.— Agassiz, 

 A., N. American Acalephae, p. 40, 1865. — Mayer, A. G., Medusae 

 of the World, vol. Ill, p. 710, pis. 75, 76, figs. 1-3, 1910 ; Publ. 109, 

 Carnegie Inst, of "Washington. 



