14 
Roper, on Biddulphia. 
it from the preceding species, to which in general outline it 
more nearly approaches. Ehrenberg's definition of Denticella 
turgida is, " Testnlse subtiliter punctatse, turgidse, processibus 
duobus, later alibus tubulosis apertis, aculeis lateribus mediis 
elongatis;""^ and Kiitzing, who considers it identical with 
his Odontella turgida, adds, " cornibus recurvatis majoribus 
obtusis.^t Although without authentic specimens, and with 
only the rather imperfect figure given in Kiitzing's 'Bacil- 
larien,^ it is impossible to speak with certainty, I think the 
description is sufficiently applicable to enable me to refer to 
these species as identical with the present form. The name, 
however, of turgida having already been appropriated to 
another and well-marked species, I have described this as 
granulata,'^ from the peculiar and distinct granular mark- 
ings of the valve. 
8. Biddulphia reticulata, n. sp., Roper. 
Valve elliptical-lanceolate, flat or slightly tumid in the 
centre, marked with large irregular hexagonal reticulations, 
the surface covered with short spines ; angular processes, 
short and subcapitate, inflated at the base; connecting 
membrane with rows of conspicuous dots, mostly parallel to 
the suture of the valve. (Plate II, figs. 13, 14, 15.) 
Var. /3, with smaller reticulations and very short obtuse 
processes. (Plate II, figs. 16, 17.) 
Marine. Trincomalee and Natal, Roper ; New Zealand, 
Dr. Walker- Arnott. 
This curious and fine species does not appear to have been 
recorded by any previous writer, and I can find none of 
Ehrenberg's figures or descriptions that lead me to suppose 
he has seen it. It diff'ers from all the other species of the 
genus in having large and distinct hexagonal reticulations, 
which are, however, rather irregular in outline and size. The 
side view of the valve is more broadly elliptical than in 
B. aurita, and wants the central inflation of that species. 
It difi'ers from B. rhombus in the absence of the pointed 
apices, and awl- shaped spines, and in the processes being 
inflated on the outer instead of the inner margin. The 
species which most nearly approaches it is Ehrenberg^s 
B. ursina (^B. Proc.,^ 1844, p. 200), of which he gives no figure, 
but describes it as large, turgid, sides covered with hairs, but 
not cellular, and central area smooth. He appears doubtful, 
however, if this is correctly placed with the Biddulphias, and 
asks, "Does it belong to Hemiaulus?" stating at the same 
* ' Ber. Acad. Pro.,' 1840, p. 207. 
t ' Spec. Alg./ p. 136. 
