GEPP—MARINE ALGA AND MARINE PHANEROGAMS. 377 
iterumque in eodem modo cruciatim ramulosis composito; ramulis ultimis vel per 
tenacula affixis vel conspicue liberis ; reticuli interstitiis in fronde juniore polygonis 
irregularibus 1-4 mm. diam.. in fronde adultiore seepe usque ad 10-20 mm. diam., 
hinc et illine per lacerationem majoribus ; margine integro. Cellulis rhacheos 7 mm. 
longis, 0°8 mm. latis ; ramulorum 0°75-1'5 mm. longis, 0°3—0°6 mm. latis. 
Cargados Carajos, 80, 45, and 47 fms. 
Of this species we have four specimens, two consisting of a mature flabellum only 
without stalk, and the other two complete but small plants, the stalk of one being about 
65 cm. long and the frond about 5 cm. The meshes of the flabellum are the largest we 
have seen in Struvea, the cells of the costa measuring as much as about 7 mm., the cells 
of the branches 3 mm., and those of the ultimate ramuli 0°75 mm. The branches and 
branchlets are opposite and the shape of the meshes is rectangular; the nodes are 
cruciate and not stellate, whereas in 8. orientalis, the following species, the branching 
at the node is stellate. 
Struvea Gardineri differs from 8. macrophylla in the smaller width and greater length 
of the costa-cells, and in the irregularity and large size of the mesh as compared with the 
regular and close mesh of S. macrophylla. S. Gardineri differs from §. orientalis in 
having an unbranched stem, an entire margin, and a looser and rectangular mesh and 
cruciate nodes, the nodes of S. oréentulis being stellate. 8. pulcherrima is the nearest 
ally in point of size, but is easily distinguished by its stellately branched reticulum of 
small regular meshes like those of some species of Jicrodictyon. 
6. Struvea orientalis, sp.n. (Plate 47. figs. 6-9.) 
Planta solitaria vel plures ex eadem basi ortz; stipite simplice vel diviso, rugoso vel 
levi, 2°5-3°75 cm. longo, ramis plerumque oppositis; fronde basi cordato 3-5-costato 
supra irregulariter expanso et mutilato vel paucilobato, usquead 4 cm. longo et lato ; 
reticulo denso e rhachi pinnatim ramosa et e ramis ad nodos stellatim egredientibus 
iterum iterumque in eodem modo stellatim ramulosis composito, ramulis fere omni- 
bus per tenacula affixis; ramulis marginalibus liberis; reticuli interstitiis parvis 
(0-1-0°3 mm. diam.) triangularibus vel polygonis et szepe per ramulos ultimos fere 
omnino impletis. Cellulis racheos infra 3:0-3°5 mm. longis, 0°5 mm. latis, sursum 
gradatim decrescentibus ; ramulorum 0°5 mm. longis, 0°25 mm. latis; cellulis ultimis 
0:2—0'4 mm. longis, 0°1-0°15 mm. latis. 
Amirante, 20-25 or more fathoms. 
This species is represented by a group of four dried plants, all growing from a common 
base, with rhizoids interwoven, and also by a single plant preserved in formalin. The 
latter specimen is simple, bears an irregularly lobed frond, with margin not entire but 
composed of free projecting branchlets (fig. 7, a), and has rather dense finely granular 
cell-contents. Three of the dried plants are two or three times brauched ; the branching 
is truly opposite, but occasionally appears to be dichotomous, owing to the removal or 
loss of one of the branches. The branches themselves are possibly the persistent basal 
costze of a denuded frond ; but we cannot be certain of this. The fronds of these plants 
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