REPORT ON THE SIPHONOPHOR^E. 235 



Ceylon. It is represented in PI. XVI. A similar species was described in 1879 by 

 Claus from the Mediterranean, as Agalmopsis utricularia (75, p. 199, Taf. xviii.). 

 Fewkes proposed for it in 1883 the generic name Calliagalma (42, xviii. p. 844); but 

 this name has been previously employed for an Insect. The peculiar and very remark- 

 able form of the tentilla distinguishes this interesting genus not only from the closely 

 allied Agalmopsis, but also from all other Agalmida?. Each tentillum bears a large 

 terminal ampulla, which is surrounded by an elegant corona of eight radial filaments. 

 The ampulla is a hydrostatic apparatus, lighter than the sea water, and directed upwards, 

 whilst the surrounding filaments are either horizontally expanded or move in different 

 directions. They form an extended net around the corm, well fitted for capturing prey. 



Lychnagalma vesicularia, n. sp. (PI. XVI.). 



Habitat. — Indian Ocean, Ceylon (Belligemma), December 1881 (Haeckel). 



Nectosome. — The swimming apparatus is similar to that of Cupulita and Agalmopsis, 

 composed of a small apical pneumatophore (figs. 1, 2, p, 4) and two opposite series of 

 about sixteen alternating nectophores (figs. 1, n, 5, 6). 



Pneumatophore. — The float is ovate, with an octoradial red-brown pigment-star on 

 the apex, and eight equidistant longitudinal ribs in the basal half. These are the 

 insertions of the eight vertical septa which divide the cavity of the pneumatophoi'e into 

 eight radial pouches (fig. 4, pq). A horizontal annular septum, similar to a diaphragm, 

 divides the pneumatosac, somewhat beyond its equator, into two unequal halves ; the 

 superior larger half contains the chitinous pneumatocyst ; the inferior smaller half is lined 

 by a greenish, air-secreting epithelium, the pneumadenia ; both halves communicate by 

 a circular opening in the diaphragm, the pneumatopyle. 



Nectophores (figs. 5, 6). — The swimming-bells are very similar to those of Cupulita 

 canariensis, rather square in the frontal view (fig. 6), irregularly pentagonal in the lateral 

 view (fig. 5). The convex dorsal face has a median rounded ridge, which fits into a 

 corresponding groove on the concave ventral face of the superjacent nectophore. From 

 the apical part of the latter arises a short triangular pedicle which attaches the bell to 

 the axial trunk. The two paired lateral facettes (on both sides of the median groove) 

 are produced into two apical horns, or nearly triangular-pyramidal auricles. The distal 

 base of the nectophore is obliquely truncate. The large nectosac is correspondingly 

 tripartite hammer-shaped, with an odd median basal or distal part, and two paired ovate 

 lateral pouches. Its four radial canals exhibit the usual shape, the two sagittal vessels 

 run simply curved in the median plane of the subumbrella, whilst the two lateral 

 vessels (figs. 5, 6, cl) are much longer and form several loops. 



Siphosome (fig. 1). — The axial trunk of the siphosome is in the expanded state four 



