248 HALF-AN-HOUR 



many seeds of interest to the microscopist. Those of Nemesia 

 especially should be studied in connection with the present speci- 

 men ; as well as the seeds of Lophospciimim^ Afaurandaya, the 

 Antirrhinums, Foxgloves, Mullens, Eye-Bright, Bartsia, etc. And 

 the closely allied order, BiGNONiACEyE, has for one of its distinc- 

 tive characters, " seeds winged," and furnishes magnificent exam- 

 ples of the structure. Fancy a seed an inch across, with a wing 

 of the same width all round ! Such is Calosa?ithes indica. Eccre- 

 vwscarpits scabej- is a well-known plant, having a winged seed 

 approaching to the latter in structure. This (structure) is caused 

 by the undue development (according to law) of some of the cells 

 composing the testa over others. It has been well described by 

 H, B. Brady in " The Quar. Jour, of Micro. Science " (Transac- 

 tions) for July, 1 86 1, p. 65, PI. VII. 



The name is differently spelt by different authorities. Lindley 

 gives it as Faulownia, and this is what I have always been used 

 to ; but I find Henfrey, in his " Elementary Course of Botany," 

 has two " Ts," thus, PaiiUoivjiia. 



Spicules of Grantia compressa. — There are seven British 

 species of Grantia described. One of their characters is to have 

 the spicula calcareous, instead of siliceous, as in most other 

 sponges, hence readily soluble in dilute acids. Grantia compressa 

 has a classic interest, from its being the form in which Dr. Grant 

 first discovered " inhalation " and " exhalation," the vital action 

 of the sponge, and so settled the controversy as to the Spox- 

 GID/E being truly animal, and not vegetable, as many had sup- 

 posed, from their peculiar inertness and vegetable-like mode of 

 growth. Bowerbank followed up these researches on " Ciliary 

 Action in the Spongiida,'" by a paper published in the " Transac- 

 tions of the Microscopical Society," Vol. III., p. 137, and it is to 

 him that we owe most of our knowledge of the wonderful elabo- 

 rateness of design in most of the sponges, with spicules of differ- 

 ing forms, according to the varying purposes of the animal eco- 

 nomy : some for building up the framework, others for purposes of 

 protection or defence, and yet others of a third order to bind 

 those named together. The tri-radiate spicula, however modified 

 by size and form, are essentially skeleton spicula ; while the simple 

 acerate form appertains more especially to the defences of the 

 animal. (Bowerbank on "Grantia Ciliata " in "Quar. Journ. of 

 Micro. Science," July^ 1859 (Transactions), pp. 79 — 84). A 

 paper of unusual interest, to which I would refer all who desire to 

 follow up the subject. 



Bugula avicularia. — Examples may be mounted with the 

 polypes fully expanded by dropping gin carefully and slowly into a 



