220 Miscellaneous. 



conidiophorous etipites, whicli resemble the basidia of the Hymeno- 

 mycetes. 



The conidia, or asexual reproductive organs of Baskliophora, when 

 placed in water at their maturity, present the remarkable fact that 

 their plasma, instead of being expelled before the complete formation 

 of the zoospores, undergoes its whole sporogonic evolution within 

 them. The zoospores move in the conidia until the apical papilla of 

 the latter, becoming absorbed, leaves them a passage into the liquid. 

 This apertiu'e, however, being much too narrow for the free passage 

 of the zoospores, they pass it, one after the other, with great difficulty, 

 by lengthening and twisting themselves with a most singular power 

 of vitality. After their escape they traverse the liquid with con- 

 siderable rapidity, but in less than an hour they stop and germinate. 



The organs of sexual reproduction in BasicUophora are formed in 

 the parenchyma of the leaves which have already presented the co- 

 nidiophorous stipites. But this parenchyma, being formed by a very 

 comjDact cellular tissue, does not allow us to ascertain clearly the re- 

 lations of the antheridia and oogonia, or to observe the phases of 

 fecundation. — Comjptes Benches, March 15, 1869, tome Ixviii. pp. 

 651-653. 



On Spatangus Easchi, Loven. 



At the meeting of Scandina^-ian naturalists at Christiauia, in July 

 1868, Prof. Loven exhibited specimens of this new species, which 

 was first discovered on the deep sea-bank of Storegzeu, off the coast 

 of Norway, as far back as 1844, by Prof. H. Rasch, of the University 

 of Christiauia. Since that time it has bceu found occasionally in 

 the same locality, and Mr. Gwyn Jeffreys has dredged it iu the Zet- 

 land seas. From the Spatangus purpureus of 0. F. MiiHer, which it 

 almost surpasses in size, it differs by its more oblong and posteriorly 

 more attenuated form and greater height, by much narrower petala, 

 by the flattened ventral surface, the prominent lip, the narrow 

 strongly keeled sternum, of almost equal breadth throughout, and 

 by the rounded, not bilobate, area semitalis, half as large as that of 

 Spatangus purpureus of the same size. The colour is dark reddish 

 brown; and the primary spines, arranged, as in Sp. purpureus, in 

 arcuate series, are shorter than in that species. 



At the same time, Prof. Loven drew attention to the fact that, in 

 very young specimens of Spatangidte, the peristomium, situated 

 much nearer the middle of the body than in the full-grown animal, 

 is exactly pentagonal, with the mouth, an oval opening in its centre, 

 surrounded by perforated plates of an irregular form. But the 

 mouth is very soon drawn backwards, and becomes transversely 

 elongated, the surrounding plates assuming their specific shapes ; 

 and when the mouth has reached the posterior side of the peristo- 

 mial pentagon, this side begins to protrude forwards and to deve- 

 lope into the vaulted lip peculiar to the Spatangidaj. This juvenile 

 pentagonal form of the peristomium is retained by the full-grown in- 

 dividual in Palceostoma and in certain fossil forms, as Echhiospatangns, 

 Holaster, and others. — Commumeated hy Prof. Loven. 



