BROWNE— MEDUSA FROM THE INDIAN OCEAN 191 



when contracted, and quadrangular when expanded. It is fairly large and occupies the 

 greater part of the top of the cavity of the umbrella. The mouth is fairly large, and has 

 four lips. There are four radial canals, without any branching. Eight tentacles (4 per- 

 radial and 4 interradial) with thick conical basal bulbs. Between every two tentacles 

 there are three marginal bulbs, very small and short, a little longer than broad, and from 

 their general appearance they evidently do not develop tentacles. A conspicuous roundish 

 dark brownish ocellus is situated on the outer side of all the basal bulbs and on all the 

 small marginal bulbs. No trace of any cordyli, cirri, or marginal sensory vesicles could be 

 seen. One of the specimens is a little smaller and younger than the other. It has only 

 two marginal bulbs between every two tentacles, and one of its interradial tentacles is 

 missing. Both specimens are badly contracted, but in a fairly good state of preservation. 



26. Leptomedusa, No. 2. 



Localities. Farquhar Group, Surface. 2 Oct. 1905, w. 1 specimen. Amirante Isles, 

 Desroches Atoll. 50—0 fms., 200—0 fms. 1(5 Oct. 1905, kk. 2 specimens. 



Description :— Umbrella hemispherical, fairly thick, i — 8 mm. in diameter. Stomach 

 small, quadrangular when expanded. Mouth with four large lips having a crenate 

 margin. Four narrow radial canals. Gonads extending over the outer half of the radial 

 canals. Tentacles 16 {perhaps more), small, with small globular basal bulbs. Three to 

 seven (usually five) elongated marginal bulbs (?) between every two tentacles. Two 

 sensory organs between every two tentacles. 



I cannot determine the genus to which these specimens belong owing to the condition 

 of the marginal bulbs. These bulbs are elongated, and vary in length. They may 

 be cirri in a state of contraction, or minute tentacles unlike the large ones, or genuine 

 bulbs. I am in favour of their being contracted cirri. The sense organs are small, about 

 large enough to contain a couple of otoliths, and are probably open sensory pits ; if so, 

 the specimens would belong to the Mitrocomidse. The tentacles are not always equi- 

 distant apart, hence the irregular number of bulbs between them. One specimen has 

 a quadrant containing six tentacles. 



27. Leptomedusa, No. 3. ' 



Localities. Nazareth Bank, Cargados Carajos, Surface. 30 Aug. 1905, i. 1 specimen. 

 Amirante Isles, Surface. 18 Oct. 1905, oo. 3 specimens. 



Description : — Umbrella rather flat, about 3 mm. in diameter. Stomach small and 

 flat, similar to that of a Phialidium. Four radial canals (one specimen with five canals) 

 without branches. Gonads sausage-shaped, along nearly the whole length of the radial 

 canals. One specimen has conspicuous ripe ova. Tentacles small and slender, about 

 40, and terminating with a small cluster of nematocysts. No signs of cirri, or rudi- 

 mentary marginal bulbs between the tentacles. No sense organs of any kind could 

 be found. 



All the specimens have rather a macerated appearance, and consequently it is not 

 safe to rely upon the absence of sense organs. 



