322 DISCOVERY REPORTS 



A. gaussi (Kluge) (see below) in the length of the zooecia, but agrees with A. nuda in the 

 size and number of its spines and the absence of giant spines. In this specimen one of 

 the distal spines commonly curves over the aperture, following the outline of the distal 

 border of the scutum. Hasenbank's supposed specimen of A. nuda (1932, p. 362) from 

 Bouvet Island clearly belonged to A. gaussi. Calvet unfortunately gave no description, 

 but his specimen came from the region of the type-locality of A. nuda and presumably 

 belonged to that species. 



A median, longitudinal, basal heterozooecium is sometimes present before a bifurca- 

 tion both in the type and in the present material. It is similar in shape to the lateral 

 basal heterozooecia (Figs. 2 D, E; see p. 325). 



2. Amastigia harmeri sp.n. 



Amastigia nuda MacGillivray, 18876, p. 200 [not A. nuda Busk, 1852]; part Harmer, 1923, 

 p. 330, pi. xvii, figs. 21, 25, pi. xix, figs. 50, 51 ; Livingstone, 1929, p. 54. 

 Station distribution. New Zealand: Sts. 934, 935. 



Geographical distribution. Victoria (MacGillivray; Harmer); New Zealand (Livingstone; 

 Discovery). 

 Holotype. Port Phillip Heads. Bracebridge Wilson Collection, 97 . 5 . 1 . 246. Figured by Harmer. 



With the exception of Fig. 24, Harmer's drawings of Amastigia nuda all represent the 

 Victorian form, which, now that a little more material of the true South American 

 A. nuda is available, is found to show certain constant differences and is here regarded 

 as a distinct species, A. harmeri. Harmer's figs. 49 and 50 show the characteristic 

 scutum which is rounded, with the proximal lobe not much larger than the distal. The 

 lumen is narrow and runs across the scutum in a line with the stalk, widening more or 

 less at the edge. 



In the type and other South American specimens of A. nuda the proximal lobe of the 

 scutum is longer and the lumen extends into it (Fig. 1 B). The cryptocyst of A. harmeri 

 is wider than that of A. nuda and is more granular. Another difference which appears 

 to be constant is the greater size, and particularly width, of the uncalcified frontal area 

 in the ectooecium in A. harmeri. The difference in the basal surface of the branch is 

 less sharply defined, but on the whole the inner rows contribute less to its formation 

 in A. harmeri, and there are nearly always some branches in which the basal surface is 

 formed entirely by the marginal zooecia. The greater part played by the marginal 

 zooecia in forming the basal surface results in their outer edges being turned more 

 basally so that the marginal avicularia, when present, are also directed more or less 

 basally instead of laterally. The differences are slight, but, as far as the evidence goes, 

 definite. 



It may reasonably be assumed that Livingstone's specimens from New Zealand 

 belonged to A. harmeri. 



3. Amastigia gaussi (Kluge). Figs. 1 A, C. 



Scrupocellaria gaussi Kluge, 1914, p. 609, pi. xxvii, figs. 9, 10 [not figs. 3 and 4]. 

 Amastigia gaussi Harmer, 1923, p. 338. 

 Amastigia nuda Hasenbank, 1932, p. 362. 



