THE MARINE ALGiE OF NEW ENGLAND. Ill 



this statement by our own observations, although Koschtsug maintains the contrary. 

 The genus Bangia, except that the cells composing the frond are arranged in cylindri- 

 cal filaments instead of expanded membranes, differs in no essential respect from Por- 

 phyra and the production of spores and antherozoids is the same. 



The development and structure of the species of this order have formed the subject of 

 a number of important papers, viz : Porphyra laciniata, in Etudes Phycologiques, by Bor- 

 net and Thuret; JStudes Anatomiques sur les Porphyra, by Jauczewski, in Annalesdes Sci- 

 ences, Ser. 5, Vol. XVII; and Ueber die Geschlechtspjlanzen von Bangia fusco-purpnrea, in 

 Pringsheim's Jahrbucher, Vol. II. In the Nereis. Am. Bor., Harvey placed Porphyra 

 and Bangia with the Ulvacete, which they resemble in so far as they consist of simpls 

 membranes and filaments some of whose cells change directly into spores. The sporee 

 of the Porphyron, however, are motionless bodies, not zoospores as in the Ulvacece, and 

 their color is not green, but brownish red. The systematic position of the order has 

 been in doubt, because, although there were well-known spores and bodies to which 

 the name of antheridia was applied, no one had succeeded iu detecting trichogynes 

 and procarps, which must necessarily exist if the Porphyreoe are to be classed with the 

 Floridece. Dr. G. Berthold, however, has recently published in the Mittheilungen aus 

 der zoologischen Station zu Neapel a communication in which he claims to have discov- 

 ered trichogyues in species of Bangia and Porphyra. According to him, the cells pro- 

 duce short trichogynes to which the antherozoids adhere, and as a result the contents 

 of the cell divide and produce the spores at once. In other words, the Porphyrece are 

 the simplest of the Florideos; a vegetative cell produces a trichogyne and is itself the 

 carpogenic cell from which the spores are formed. Dr. Berthold goes further and says 

 that some of the spores are nonsexual and are true tetraspores, but his article is not 

 accompanied by illustrations. Bornet, to a certain extent following Cohn, suggests a 

 possible connection of the Floridew with the Phycuchromacece by means of the Porphy- 

 rew. Admitting that Erythrotrichia and Goniotrichum ar® related to Porphyra and 

 Bangia, we have iu Goniotrichum algte composed of rose-colored discoid al cells packed 

 in a thick gelatinous tube, from which they escape much as in some of the Phycochrom- 

 acete. 



PORPHYRA, Ag. 



(From iropyvpa, a purple dye.) 



Fronds gelatinous, membranaceous, composed of a single layer of 

 brownish-red cells, those near the base sending out root-like processes; 

 spores borne near the margin of frond, eight arising from a single mother- 

 cell ; antheridia marginal, consisting of 32-G4 spherical, colorless an- 

 therozoids. 



A small genus, the species of which are characterized by the relative position of the 

 spores and antheridia and by the shape of the frond. Most of the species have been 

 founded on variations in the outliue of the frond, and recent writers agree iu uniting 

 many of the species of the older algologists. 



P. laciniata, Ag. — Laver. (P. linearis, Grev. ; Phyc. Brit., PI. 211, 

 Fig. 2. — P. vulgaris, Harv., Phyc. Brit., PI. 211, Fig. 1. — P. laciniata, 

 Harv., Phyc. Brit., PI. 92 ; Etudes Phycol., PI. 31.) 



Fronds three inches to a foot and a half long, persistent thr oughout 

 the year, color livid purple, substance gelatinous but firm, at first 

 linear, but becoming widely expanded and finally much lobed and 

 laciniate ; antheridia and spores formiug a marginal zone, usually borne 



