REPORT ON THE TETRACTINELLIDA. 
319 
Although the specimens of the Challenger collection are in a dried state, I cut and 
stained sections of them ; these showed that the tubular processes are lined by reticula- 
tion of collenchyma, but nothing further (PL XXXVII. fig. 24). The specimens from 
Professor Agassiz were also cut, and the character of the slices is shown in fig. 23, PI. 
XXXVII. They are sufficiently unpromising ; nevertheless, in some of the larger patches 
of tissue I was able to make out the presence of flagellated chambers, as shown in fig. 25, 
PI. XXXVII. , and also of oval granular cells embedded in a stained collenchyma, similar 
to the prevailing tissue of Azorica pfeifferse. The ectosomal desmas tear away in the 
process of cutting along with the outer layer of skin. Schmidt states that the pores of 
Siphonidium ramosum are generally distributed over the surface of the sponge ; neither 
in Professor Agassiz’s nor in the Challenger specimens, however, could I find any traces of 
pores, and I am still in doubt whether the tubular processes may not some perform an 
incurrent and others an excurrent function. 
The development of the desma is illustrated by figs. 9-15, PI. XXXVIL, commencing 
with the crepidial strongyle (fig. 9), which in fig. 14 is seen enclosed within the epirabd. 
The zygosis of two desmas of the normal kind is shown in fig. 21, which is also intended 
to illustrate the mode of occurrence of small desmas which arise as an aftergrowth, filling 
up the meshes of the chief skeleton. The secondary desma is seen at the left hand 
lower corner of the illustration pointing towards the number 21. 
Suborder II. ANOPLIA. 
Lithistida in which special ectosomal spicules and microscleres are absent. 
Family I. Azoeicid^. 
Anoplia in which the desmas are monocrepid. 
Genus 1. Azorica, Carter. 
The pores and oscules are simple, and are borne on opposite surfaces of the plate-like 
sponge. 
Azorica pfeifferse, Carter (PL XXXVI. ). 
Azorica pfeifferx, Carter, Ann. and Mag. Nat. Hist. 1, ser. 4, vol. xii. pp. 438, 442, 1873; vol. 
xviii. p. 466, 1876. 
,, „ Zittel, Abhandl. d. k. baier. Akad. d. Wiss., Bd. i. pp. 103, 121, 1878. 
Sponge (PL XXXVI. fig. 1). — A thin plate, erect, much folded, with a rounded 
upper margin. Surface generally hispid, with long, slender, oxeate spicules ; inner sur- 
