466 PROCEEDINGS OP THE ACADEMY OP 



high. This desire to get out of the water if possible, lie had before 

 suggested as the cause of those peculiar productions of the roots 

 of cypress known as cypress knees. Whenever the tree found 

 itself in land covered by water these knees were thrown up above 

 the surface, till the water had the appearance of being covered by 

 flocks of huge water birds ; but when the trees were on land from 

 which the water is now drained away, the knees did not appear. 



The Florida moss, Tillandsia usneoides. In regard to this 

 plant, Mr. Meehan thought little was known of its history or 

 development. Some even supposed it to be a parasite. He had 

 been able to ascertain that the seed germinated when it found 

 itself in the hollow crotch of a tree in which vegetable mould had 

 collected. From this young plant hair-like stolons or runners pro- 

 ceeded with buds at every few inches, which buds in time pushed 

 forth into the gray green leaves and stems popularly known as 

 moss. These branches, as they hung, did not send out the hair- 

 like runners, but if they became detached from the original stock 

 and on another branch would do so. It appeared, however, that 

 propagation from seed w T as extremely rare the chief increase be- 

 ing by pieces of the branches blown b} r storms, or carried by other 

 agencies to other locations. Unless already on tall trees so as to 

 be blown down, it was difficult for the " moss" to travel up the 

 tree. As in the case of the grape-vines on the tall trees of this 

 region, it is carried up as the trees grow. On large old cypress 

 trees, it is probable the whole colony is formed of a few original 

 plants of many years of age. Trees which grow rapidly and had 

 chiefly erect branches, such as willows, on which the "moss" would 

 not hang easily, were chiefly free from it ; the horizontal branches 

 of the c}*press were very favorable to the attachment, and the 

 somewhat pendulous branchlets of the live oak well calculated for 

 entanglement with the loose flowing masses of the Tillandsia, and 

 hence it was usualby abundant on these trees. That it was merely 

 an epiphyte and not a parasite was clear from its growing as well 

 on telegraph wires as on trees. For a long distance above New 

 Orleans it might, be seen attached to the wires, on which it had 

 evidentl}- been originally blown from the trees. His attention had 

 been called to this fact 'by Col. Hillyard, one of the officers of the 

 railroad, who, without any great scientific pretensions, was yet an 

 acute observer, and who had noticed the little patches on the wire 

 getting larger by growth from 3'ear to year as well as if growing 

 on trees. This fact, of course, shows the plant to be a mere epi- 

 phyte in character. 



Notes on the Genus Calillus, Brong. At the request of T. A. 

 Conrad, the following note was read: 



The genus Calillus was separated from Inoceramus, by Brong- 

 niart, but the name had been previously given to a fresh-water 

 group, by Humphrey (Navicula Lam.). I have described and 



