68 
PATAGONIAN EXPEDITIONS : PALEONTOLOGY. 
Cyclostomata. 
Fam. LI CHENO PORI DAL Sm. 
Gen. RETICULIPORA d’Orb. em. Wat. 
12. Reticulipora patagonica Ortmann. 
PI. XII, Fig. 2«A 
1900 Reticulipora patagonica Ortmann, in: Amer. Journ. Sci., v. 10, p. 
37°- 
Zoarium reticulate, fenestrae of the reticulations 2-4 mm long, and 1-2 
mm broad, irregular. Branches much compressed in section, about 2 
mm deep. Broad lateral surfaces of the branches with slightly exserted, 
tubular zooecia, which are rather crowded and form irregular transverse 
rows. Besides the zooecial openings there are smaller, non-tubular ones 
at the sides of the branches. On the front of the branches a median 
lamina rises as a distinct narrow median ridge. On the back part, the 
branches are rounded, and show very small openings. 
Remarks: In the possession of intermediate pores this species does not 
correspond to the original diagnosis of the genus given by d'Orbigny 
(1859, p. 903), but it agrees with Waters’ conception of Reticulipora . For 
the same reason the present species and the genus Reticulipora of Waters 
cannot be united with Idmonea, as Zittel does (1880, p. 599)- I leave 
our species in the genus Reticulipora , since it comes extremely near to 
Ret. transennata Waters. 
Record of specimens: Mouth of Santa Cruz River; fragments of about 
10 colonies. 
Affinities : This species is very closely allied to Reticulipora transennata 
Waters (1884, p. 689, pi. 30, f. 2, 3, 6, 7), from Aldinga, South Australia, 
which locality is regarded as Eocene. Indeed, it resembles this one so 
much that I entertain some doubt as to the specific difference of both. 
The only differences I am able to point out are: the branches of the 
zoarium seem to be stronger in our species (compare fig. 3 of Waters), 
and the zooecial openings appear to be more crowded (see fig. 7, 1. c.). 
