450 Transactions. — Botany. 



To this I append with very great pleasure the interesting 

 and valuable detailed microscopical examination of the spo- 

 rangia and their contents kindly and purposely made for me by 

 my friend Dr. Spencer, with the aid of his powerful micro- 

 scope ; who thus writes : "I have had another hour with the 

 pretty little Iso'etes. 1st. The sporangium at the base of the 

 leaf is an ovoid body, slightly flattened at the sides, |in. long 

 by iV^^- hi-'o^'Cl ; in some cases with a Y'^i^^^'k at the end as 

 though this were the shape of the opening when ripe. Within 

 this are the macrospores. Out of one of the sporangia, which 

 I divided, I counted twenty of these bodies. They vary in 

 size from g^jin. to ij-^ii'i-. in diameter ; a few are even smaller 

 than this. They are not uniform in shape, but for the most 

 part give the idea of being segments of spheres ; some are 

 hemispherical, others, and by far the larger number, have the 

 appearance of hemispheres either divided into four parts or 

 their inner sides flattened by mutual compression into a solid 

 triangle with one face forming a segment of a sphere. You 

 may get an idea of the shape by dividing an apple or potato 

 into halves, then laying one half on its flat face, dividing it again 

 into four by a crucial incision. Each of these bodies is com- 

 posed of three tunics; the outer semi-transparent, membranous, 

 brownish in colour, showing ridges and furrows, which seem to 

 result from pressure on the middle coat. The middle coat is 

 white, thick and ridged along the margins, with the facet 

 sculptured into figures of various shapes. Under the micro- 

 scope the effect is very beautiful, and the original must be seen 

 to appreciate it. The innermost coat is also white, but smooth. 

 Within it are the microspores, minute spherical or ovoid 

 bodies -g^^i^^in.-^^L-^in. in diameter, pellucid, having much 

 the appearance of starch-grains or oil-globules. I put on the 

 polariscope, but they did not respond, and therefore are not 

 the former ; and I washed them with ether, but they did not 

 disappear, and therefore they are not the latter. The effect of 

 the latter operation was to make the contour much more dis- 

 tinct, and also to relieve it of a brownish coloration, so that 

 I am disposed to think they must have been surrounded by or 

 contained some oily matter. They are very numerous." 



Hah. " In sheltered bays, Lake Taupo, in 2ft.-10ft. water 

 with sandy bottom." Mr. C. J. Norton, June, 1889. 



Obs. I. The examination, &c., of this little plant has oc- 

 cupied no small amount of both time and labour, with also the 

 scattered necessary references ; partly, however, owing to the 

 fact of the lot I had received from Mr. Norton arriving in a 

 much damaged state, being mostly beached specimens of 

 plants torn up and cast on shore in a furious gale. It was 

 pretty apparent, notwithstanding, that they differed from our 

 other (described) New Zealand species, as also, on fuller 



