32 GEAF ZU SOLMS-LALBACH— MONOGKAPH OF THE ACETABULAEIE^. 



Polyphysa sjncata, Kiitz. Tab. Phyc. vol. xvi. t. i. fig. 2 {im6).—Pleio2jhi/sa spicata, 

 Sond. in E. v. Mueller's fragment. Phytogr. Austr. Suppl. (solum iiomen). 



Hah. On the shores of New Caledonia, mouth of the Elver Massioncoue [Balansa, 

 no. 2640), lib. Thuret ; on madrepores at Ina, 1863 {Vieillard, N. Cal. no. 1961, Hb. 

 Thuret, Berlin ; Vieillard, N. Cal. no. 13 in Hb. Brit. Mus.). 



This species is very similar to the other, but is to be distinguished by the smaller 

 number and the cohering of its calcified spores, which appear in a fresh state like a small 

 fi-agment of lime of irregularly rounded form. The young plant also has a somewhat 

 different habit, but I have seen it only in a few individuals {Vieillard, 1901). 



III. CHALMASIA, nov. gen. 



Piscus fertilis terminalis e radiis liberis incrustatione tantum coalitis format us. Corona 

 inferior nulla ; sporse liberse membrana crassa valde incrustata insignes. 

 Pertile cap terminal, composed of free, wedge-shaped rays, united only by the calcifi- 

 cation ; corona inferior wanting ; segments of the corona superior not touching each 

 other laterally, knob-shaped, and not sharply delimited towards the base ; spores free, with 

 thick, much calcified membrane, and coarse cuticularized outer layer. 



1. Chalmasia aktillana, sp. unica, char. gen. 



Cap infundibidiform, rays free, 26-32, with cylindrical basal portion which bears the 

 coronal prominences in the form of an elevated ridge : this has the hair-scars either 

 a pair obliquely or three in a triangle on the laterally compressed point. Sporangium 

 covered externally all round with thin, irregularly outlined, easily detachable flakes of 

 incrustation, vesicular and inflated, cut off at the outer margin, with an obtuse bulging 

 projection : spores filling the whole sporangium, approximately globular, chalk-white 

 from the strong calcification of the membrane. 



Size: diam. of cap about 6 mm. ; breadth of corona 0*18 mm. ; spore diam. (measured 

 after decalcification) 0-15 mm. (Plate III. figs. 2, 3, 5.) 



Kah. "West Indies {Agassiz !). (Hb. Thuret, misit Farloic.) 



The few specimens of this very remarkable plant unfortunately lack precise 

 localization*. They are besides very imperfect, and consist merely of completely ripe, 

 torn -off fertile whorls, to which is attached a longer or shorter stalk. Its habit is that of 

 Acetabuloides — indeed they were called A. crenulata. In the absence of the corona 

 inferior they agree Avith Polyphysa, but in spore-structure completely with Rallcoryne. 

 On account of the general structure of the fertile shoot, however, the plant cannot well 

 be placed in the latter genus. 



IV. ACICULAEIA, H'Archiac, in Mem. de la Soc. geol. de 

 Prance, vol. v. pt. 2 (1813). 

 Discus fertilis terminalis e radiis inter se conjimctis formatus, coronis et inferiore et 

 superiore prteditis, sporse massa mucosa calce incrustata coalita), pro radio spiculam 

 solidam cuneatam formantes. 



* Farlow writes to me that lie received them from Comte Pourtales, who accompanied Agassiz on one of his expe- 

 ditions, and could only obtain this information with them,— that they were dredged south of the coast of Florida. 



