Squamariacece 



Order II. CRYPTO NEMIACE^. 



The fertilized carpogonium sends out a long, branched oobh-- 

 tema-filarnent, the terminal cells of each branch conjugating with 

 an auxiliary cell. From the latter the gonimoblasts arise. 



Family 1. SQUAMARIACE.E. 



This family consists of a small group of marine, or rarely fresh- 

 water Algae, which are minute, flat, gelatinous or membranous 

 expansions, commonly encrusting stones, 

 shells, or larger Algae. The thallus usually 

 consists of dense, vertically arranged cell- 

 filaments. Tetrasporangia are formed in 

 various ways, and often give the surface of 

 the thallus quite a verruculate appearance. 

 The sexual organs are developed in cavities 

 or ' conceptacles ' in the upper surface of the 

 thallus. After the fertilization of the carpo- 

 gonia these ' conceptacles ' contain numerous 

 cystocarps. 



Genus Hildenbrandtia Nardo, 1845. 

 This genus consists of a crustaceous expanded 

 thallus, of a blood-red, dark red, rose, or 

 brown colour, firmly adhering to rocks and 

 stones on the sea-shore or in rivers and 

 streams. The thallus is composed of compact, vertically arranged 

 cell-filaments, with subcubical or oblong cells. The cell-walls are 

 colourless and strong. 



There is only one British freshwater species H. ri>->il<i ,-!.< (Liebin.) .T. A-, 

 (fig. 4) which occurs as dark red patches on rocks and stones in streams and 

 dripping places. 



Fig. 4. Hildenbrandt- 

 ia rivulari* (Liebin.) J. 

 Ag., from Shipley Glen, 

 W. Yorks. A, section 

 of thallus. B, surface 

 view (x400). C, two 

 cells showing the chro- 

 matophores ( x 800). 



