ALG^ CONTINUED: CLASSIFICATION. 



173 



duster called the sporocarp, which means spore -fruit or spore-fruit body. 

 In Batrachospermum it is seen as a compact tuft in the loose branching, in 

 Nemalion it lies in the surface of the cortex, \\'hile in Lemanea the sporo- 

 carps lie at different positions in the hollow tube of the sexual shoot. 



376. Gonidia in the red algae. — The common type of gonidium in the red 

 alg;e is found in the letraspores. \ single mother cell divides into four cells 

 arranged usually in the form of tetrads within the tetrasporangiitm. In 

 Callithamnion the tetrasporangium is exposed. In Polysiphonia, RhaVj- 



Fig. 1 84. 

 A red alga (CalUthamnion), showing spor- 

 angium .-1 , and the tetraspores discharged 



B. (.\ftLT Thuret.) 



i-it,'. 1S5. 

 Gracilana, portion of frond, 

 showing position of cystocarps. 



Fig. 186. 

 Gracilaria, section of cysto- 

 carp showing spares. 



donia, Gracilaria, etc., it is imbedded in the cortex. In Batrachospermum 

 there are monosporangia, each monosporangium containing a single goni- 

 dium, while in Lemanea, and according to some also in Nemalion, gonidia 

 are wanting. 



