386 bulletin: museum of comparative zoology. 



in good condition, it is probably safe to say that such organs are lack- 

 ing. But otocysts are so easily destroyed that the possibility that they 

 were present but have been lost, must be recognized. This is not true 

 of the solid marginal clubs, or cordyli, characteristic of the Laodiceidae, 

 which are equally wanting in Cyclocanna. I should emphasize the 

 fact that the small marginal organs of this genus are true, hollow 

 tentacles, though they somewhat resemble cordyli in general appear- 

 ance. There are no true ocelli. 



Color. The pigmentation of Cyclocanna is extremely characteristic 

 and striking, the interradial walls of the manubrium, except for lip and 

 immediate basal portion, being very dark gray, almost black, and ex- 

 tremely opaque, the result of great numbers of minute black pigment- 

 granules crowded together in the ectoderm (Plate 3, fig. 2, 3). These 

 granules occur along the perradii as well, but in such small numbers as 

 to be hardly appreciable there, the result being that the perradii are 

 extremely conspicuous, as white bands on the dark manubrium. The 

 lip too, and the immediate base of the manubrium are likewise color- 

 less, though opaque, at least in the preserved state. And this is also 

 true of the inner, endodermal gastric wall. Black pigment-granules 

 likewise occur in such numbers in the ectoderm of the oral sides of the 

 small tentacles that these organs, are dark gray, often nearly black, 

 in oral view. And though the pigmentation is not sharply defined, the 

 granules spreading in small numbers out over the neighboring parts 

 of the marginal thickenings from the tentacles (Plate 3, fig. 5), they 

 are confined to the immediate neighborhood of the latter, the intervals 

 between the tentacles, as well as the neighboring velum, being colorless. 

 Black pigment is likewise present on the oral side of the bases of the 

 large radial tentacles, but these are in such poor condition that its 

 extent is doubtful. Pigmentation is confined to the oral, (axial), sur- 

 faces of the marginal organs, the aboral, (abaxial), surfaces being 

 colorless. The gonads of both specimens are still salmon-pink after 

 two months in formalin. 



