516 



MEDUSAE OF THE WORLD. 



Chiropsalmus quadrigatus Haeckel. 

 Chiropsalmus quadrigatus, HAECKEL, 1880, Syst. der MeJusen, p. 447. 



The following description is based upon a study of six specimens obtained in a seine 



by the U. S. Bureau of Fisheries 

 steamer Albatross among the Phil- 

 ippine Islands, from January to 

 June, 1908. 



Bell dome-like and 4-sided, with 

 an evenly rounded, aboral apex. 70 

 to 100 mm. high, 80 to 100 mm. wide 

 at level of velarium. There are 4 

 hand-shaped, interradial pedalia, 

 laterally flattened, which arise from 

 the sides of the bell at a short dis- 

 tance above the velar margin. 

 These pedalia are about 30 mm. 

 long and n mm. wide, and each 

 bears 5 to 9 finger-shaped terminal 

 projections which give rise to an 

 equal number of long, flexible, hol- 

 low tentacles. These tentacles are 

 thickly but somewhat irregularly 

 ringed with nematocysts. They 

 vary in length, but the longest when 

 contracted are about 150 mm. long. 

 The pedalia of a medusa 100 mm. 

 wide were each 47 mm. long and 

 21 mm. wide. 



The 4 perradial sense-clubs are 

 set within covered niches in thesides 

 of the bell about 14 mm. above the 

 velar margin. Each sense-club con- 

 tains an entodermal, terminal, abax- 

 ial mass of concretions and on its 

 inner side are 6 eye-spots. The 2 

 median eyes have each a prominent 

 convex lens, but the 4 smaller, lat- 

 eral eyes are merely pigmented 

 ocelli. The eyes are arranged so as 

 toviewobjects withinthe bell-cavity. 

 The velarium is 13 mm. wide and supported by 4 bracket-like perradial frenulae. There 

 are about 50 dendritic, non-anastomosing velar canals, 12 to 15 in each quadrant. The 

 velarium is diaphragm-like and does not hang downward beyond the velar margin but stretches 

 flatly across tending to close the opening of the bell-cavity. 



The wide central stomach is only about 20 mm. long and there are 4 lanceolate lips 

 with entire, simple margins. The 4 perradial sides of the cruciform stomach are much flattened 

 and form the so-called "mesenteries" of Haeckel, bridging across, bracket-like, between the 

 subumbrella and the 4-sided cesophagus. 4 pairs of gastric saccules arise from the perradial 

 sides of the stomach and project downward into the bell-cavity (c. fig. 331). Each saccule is 

 laterally flattened, cock's-comb-shaped, with an irregularly notched margin, and is about 

 20 mm. long and 1 1 mm. wide. A solid, gelatinous projection extends downward so as to fill 

 the greater part of the cavity of each gastric saccule. 



There are 4 long, interradial bands of gastric cirri marking the borders of the central 

 stomach. These cirri are fusiform, simple, sharp-pointed, and unbranched and arise in 4 or 

 5 rows. Each cirrus is about 3 mm. long. 



FIG. 331. Chtropsolntus quadfisafus Haeckel, side view of half-grown 

 medusa, half natural size. Drawn by the author, from a preserved 

 specimen collected by the Albatross. 

 A, enlarged side view of sense-club. B, inner side of sense-club. 



C, oral view of stomach showing the 4 lips and 8 gastric sacs. 



D, enlarged view of gastric cirri. E, side view of a pedalium 

 with all but one of the tentacles cut across. 



