10 Vol. XLIir., Art. 1.— K. Yenclo : 



tion between the old and new cortex, as alluded to above, is sharp 

 and clear, especially when we treat the sections in a staining 

 material. It may be well called " annual ring " in agreement 

 with phanerogam taxonomists. 



The length of the stipes varies considerably according to the 

 species and to the condition of place where the plant grows. 

 Alaria Pylaii Gkev. is characterized by having the stipe several 

 inches or even more than a foot in length. But in most species 

 of Alaria it hardly exceeds a few inches before the plant begins 

 to bear sporophylls. A typical stipe of Alaria is terete or cylin- 

 drical at the lowermost part just above the holdfast. It becomes 

 gently compressed upwards, more or less broadening at the same 

 time until it is suddenly narrowed near the transition region. The 

 first sporophyll appears as a ligulate proliferation at a point generally 

 above the middle point of the post-embryonal stipe. New sporo- 

 phylls are given rise successively above the older ones while the 

 stipe gains in length at the transition point by stipo- frondai 

 growth. The lower naked part of the stipe later grows in thick- 

 ness, but keeps the length >of the post -embryonal stage. In a 

 gigantic form such as Alaria fistulosa, several dozens of sporophylls 

 may be already formed before the lowermost one has become 

 soriferous. But in others, there are not so many sporophylls at 

 one time. The oldest ones usually avop off before the plant 

 attains its most vigorous state of growth. When the sporophylls 

 fall away, the greater part of the length of the petioles accompany 

 them, leaving but a small part as verruculose protuberances on 

 the margins of the stipe. As the frond grows further and the 

 stipe increases in length in the transition region, new sporophylls 

 are added successively above, and the lower part of the stipe 

 becomes cylindrical, obliterating the verruculose protuberances. 



