PERIPHYLLOPSIS BRAUEKI. 29 



The ring muscle, though distinguisliable, is very weak, as in Atorella, a 

 condition apparently normal, since it shows no sign of injury, but presents a 

 very uniform condition throughout its entire course. This structure was 

 not distinguished in the "Valdivia" specimen. 



The distal portion of the stomach is much battered, but both its basal part 

 and the entire peripheral canal system are intact. In its basal outline the 

 stomach resembles Atolla rather than Periphylla. The four septal nodes 

 forming its sides (PI. 12, fig. 1) extend so far centrally that they nearly 

 divide the floor of the stomach into as many petal-like compartments. The 

 gastric cirri, between eighty and one hundred in number, are arranged in 

 continuous series as is shown on PI. 12, fig. 1. The peripheral canal 

 system, shown in PI. 12, fig. 1, corresponds closely to that of Periphylla, 

 and is typical of the family. The ring sinus is about 10 mm. broad. 

 Twenty-four broad radial canals, one in the radius of each rhopalium and 

 of each tentacle extend outward from it (PI. 12, fig. 1, cr., ct.). Each 

 canal divides at the base of its corresponding rhopalium or tentacle, one 

 branch running into the lappet on either side, and there uniting with the 

 branch of the neighboring canal, thus forming a continuous festoon canal. 

 In two instances the septum between two adjacent radial canals is partially 

 subdivided by a short blind canal arising from the ring sinus. The occur- 

 rence of these structures does not, in my opinion, point to a future formation 

 of new tentacles, since the structure of the gonads shows clearly that the 

 specimen was senescent ; but probably indicates merely sporadic local de- 

 lamination of the essentially double vascular endoderm layer in the septal 

 regions. 



The distal part of the stomach, though much torn, was evidently of con- 

 siderable length, with thick, stiff walls. The lips are entirely destroyed. 



The gonads are empty, but their positions and form are clearly visible, 

 and their covering layers of tissue are intact, a fact suggesting that their 

 emptiness is due to the natural discharge of their contents. They are oval 

 in outline, eight in number as in all Periphyllidae, and equidistant one from 

 another (PI. 12, fig. l). 



The color of the species, as it appeared in the fresh specimen, is rep- 

 resented on PI. 9, fig. 1. The entire endodermal system is pigmented, 

 the stomach densely and the peripheral canals more faintly, with the deep 

 chocolate-red color so characteristic of the Medusae of the intermediate 

 depths. 



