262 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 4 



Aglaophenia venusta, new species 

 Plate 32, Fig. 30 



Trophosome. — Colonies, loosely clustered, up to 7 cm in length, arise 

 from a stolon which is slightly reticulated, but the hydrocladia are rela- 

 tively short, often not more than 3 mm, and they are regular, hence the 

 whole colony is quite graceful. As is often the case in this genus, the stem 

 is much darker horn-colored than the hydrocladia. The stem is divided 

 into regular, short internodes by well marked, transverse nodes; as each 

 internode gives rise to a hydrocladium, the hydrocladia are closer together 

 than usual; they arise from the face of the internode not far from the 

 middle, hence at their origin, two in succession make an acute angle with 

 each other; the principal portions of the hydrocladia on the two sides are 

 nearly in the same plane. The internodes of the hydrocladium are rela- 

 tively short as well. The partial septa, 2 of them, are well marked but 

 are short; the nodes are transverse. The hydrotheca is much similar to 

 that of A. longicarpa, although it is noticeably smaller, less than 1^ 

 times as long as broad, increasing in diameter from base to margin; the 

 septum is short but distinct. There are 9 teeth on the margin ; the median 

 is small and sharp-pointed, erect or slightly retrorse; the first lateral is 

 the longest, projecting forward slightly, so that the tip of the median may 

 sometimes be seen past it ; the remaining laterals are more rounded, and 

 although they are distinct, they are not deeply cut. The supracalycine 

 nematophores are suitably small, projecting outward and then upward, 

 just reaching the margin of the hydrotheca; the mesial nematophore is 

 not far from being as long as the face of the hydrotheca; less than one- 

 fourth is fre€, projecting but little. The 3 nematophores on the cauline 

 internode are similarly tubular ; as the internode is short, these are placed 

 quite close together. 



Gonosome. — The corbula has not the great length that it has in A. 

 longicarpa, but it is relatively and actually stouter, little more than twice 

 as long as deep; it has 8-10 pairs of leaves. There are 2 hydrothecae 

 between the corbula and the stem. The corbulae are not particularly 

 plentiful in any one colony, but they are well scattered throughout the 

 length of the stem. 



Distribution. — Station 970-39, Magdalena Island, Tres Marias Is- 

 lands, Mexico, 13 fathoms. 



