154 MARINE BIOLOGY OF THE SUDANESE RED SEA. 
In Reteporide they appear to be quite constant and well developed large 
sacs ; also in the holostomatous Celleporide, which should be separated as 
FToloporella *, they are very long and tubular, or even irregularly twisted 
(Pl. 16. fig. 7). In Smittia they are apparently always found, being very 
minute sacs close up to the tentacular sheath (PI. 15. fig. 11). In Lepralia 
they occur well developed in some species, though not so large as in Retepora, 
and it is one of the characters which must be used in endeavouring to bring 
the three genera Schizoporella, Lepralia, and Cellepora into better order. 
In Schizoporella they occur in some species, but I have so far only found 
them in species which have no muscular attachment close to the border, while 
in those with the muscular dots nearer together, as in S. unicornis, they have 
not been found. 
It will be seen that in a large number of species each gland is divided into 
two distinct parts, but the most highly developed of all is that of Lepralia 
occlusa, Busk ; then we pass to those with a terminal sac, as in Schizoporella 
sanguinea, Norm. ; next to those with only the one part, which may develop 
into long contorted tubes as in Holoporella vermiformis, nov. (Pl. 16. fig. 7) ; 
or, finally, they may occur as only a pair of small globes, consisting of but 
few cells close to the tentacular sheath, as in Smittza. In Cellepora caminata, 
Waters, the glands are tubular, forming !a lobe. This interesting species 
should be further studied in fresh material. The glands of Lepralia eliminata, 
Waters, are perhaps the most curious yet met with, and I therefore add 
figures (PI. 14. figs. 10, 11). At the end of the first tubular portion, and 
with only a slight attachment, there is a round globe which in sections is 
homogeneous or contains in parts, usually the upper part, stout rods or 
vermiform bodies. These rods may be seen in the upper portion of the duct 
or gland, and occasionally there seem to be traces of large cells in the globe. 
The glands of this species I am unable to understand. 
In various species I have seen a few abnormal growths of a smaller gland 
attached to the larger one, as figured in my Suppl. ‘ Challenger’ Report, 
pl. iti. fig. 15, but this structure is rare. 
In the avicularia there are also glands in a large number of species, and 
I figured those of Lepralia foliacea, Hl. & Sol.f (figs. 1, 4,5), and Retepora 
cellulosa, L.f (fig. 14). They also occur in the avicularia of Lepralia mar- 
garitifera, Q. & G., J. clivosa, Waters, Microporella ciliata var., Smitica 
trispinosa, Johnst., Porella plana, Hincks, P. acutirostris, Smitt, &e. The 
avicularian glands have also similar yellowish homogeneous contents, some- 
times with semitransparent bodies with more or less straight edges, as in 
* In the ‘ Challenger’ Cedlepora hastigera, B., there are enormous glands extending nearly 
the length of the zocecium, and again turned back about half this length, but the state of 
the Brit. Mus. slides does not permit of further study. 
t Journ. Linn. Soc., Zool. vol. xxiv (1892) pl. 19. figs. 1, 4, 5, 14. 
