1916] Robinson, — A Monstrosity of Arisaema triphyllum 223 



of which is not ut first sight evident. However, examination shows 

 that it is undoubtedly an imperfectly developed spathe, which ap- 

 pears to have been caught in this position while the inflorescence was 

 in the bud-stage, and in consequence to have been distorted in its 

 subsequent development. 



As in the case of most monstrosities, no environmental factor was 

 observed which would in any way account for the deformity. The 

 scape is a little more than ordinarily robust, as is also the spadix, but 

 both are symmetrical and show no flattening, grooving, or other evi- 

 dence of fasciation. 



The secondary spathes are wholly sterile. As will be seen from 

 the admirable sketch drawn by Air. F. Schuyler Mathews the spathes 

 are of varying breadth and in some cases rather tightly in-rolled. 

 Some are also considerably shorter than the others, and these being 

 at the back in the interior of the main spathe cannot be shown in the 

 drawing. 



Exceedingly few teratological developments have been observed, 

 or at least recorded, in Arisaema triphyllum and when it is borne in 

 mind that the species is common, widely distributed, conspicuous and 

 generally known, ami also that it flowers at a time when collec- 

 tors are in the first enthusiasm of a new open season, this is rather 

 surprising. 



The late Prof. W, W. Bailey l described briefly a garden specimen 

 in which two spadices were observed in a single spathe. Later 2 he 

 mentioned a specimen sent to him by Miss Eloise Butler of Minne- 

 apolis, in which a double spathe included a single spadix. Miss 

 Alice G. Clark 3 describes and figures a more complicated case (found 

 at East Weymouth, Massachusetts) in which two somewhat unsym- 

 metrically related spathes enclosed three somewhat flattened and 

 grooved spadices. 



Prof. Packard has most kindly given to the Gray Herbarium the 

 monstrosity here described and it has been preserved in alcohol. 

 Gray Herbarium. 



i Bull. Torr. Rot. Club. ix. 91 (1882). 

 - hot. Gaz. ix. 177 (1884). 

 » Rhodora, vi. 103 (1904). 



