Prof. G. Gulliver on the Leaf-cells of Hymenophylluni. 109 



the absence of lateral thoracic spines compels us to treat it as a 

 member of the Alcidion group *. 



[To be continued.] 



XII. — On the Leaf-Cells of the British Species of Hymeno- 

 phyllum. By George Gulliver, F.R.S., Professor of Ana- 

 tomy and Physiology to the Royal College of Surgeons. 



A comparative examination of the leaf-cells of this genus seems 

 to be a desideratum, which I can only attempt to supply, at 

 present, as far as regards the British plants. 



There is nothing satisfactory on the subject in the works of 

 Sir James Edward Smith and Mr. Sowerby. In the ' English 

 Botany' no mention occurs of the cells; and the figure given 

 of those of H. Wilsoni (t. 2686) incorrectly represents the inter- 

 cellular spaces nearly or quite as large as the cells, though the 

 oval form is truly depicted, but without the slightest indication 

 of any difference in this respect between the two species. The 

 same remark is applicable to the descriptions and plate in the 



* The following species also belong to the second section oi Alcidion : — 

 A. bicristatum. Elongatum, postice sensim attenuatum, olivaceo-griseum, 

 fusco varium. Cajjut olivaceura. Antennae infra parce setosae, articulo 

 basali angulo inferiore apicali producto, olivaceo-brunneae, articulis basi 

 pallidis. Thorax dorso obtuse tuberculatus, antice et postice punctatus, 

 olivaceo-griseus, subsericeus. Elytra elongata, depressa, postice sensim 

 attenuata, apice oblique sinuato-truncata, angulis externis productis ; 

 lateribus et disco obtuse carinatis ; carinis centrobasalibus parum pro- 

 minentibus, singulis cristis duabus pilorum nigrorura ornatis ; elytris 

 utrinque penicillis minutis atris in duplici serie (altera suturali, altera 

 obliqua discoidali) notatis : olivaceo-grisea, tertia parte posteriore satu- 

 ratiore griseo lineata, marginibus nigro punctatis. Corpus subtus gri- 

 seuna, pedibus olivaceo-griseis nigro punctatis, femoribus basi testaceis. 

 Abdomen foeminse segmento ultimo dorsali apice attenuato producto, 

 maris rotundato medio emarginato. Long. 5 lin. S ? . Hab. Rio 

 Janeiro. (Coll. Squires.) 

 A. trivittatum. Elongatum, depressum, postice sensim attenuatum, brun- 

 neo-sericeum, vittis et maculis fusco-atris ornatum. Caput fuscum. 

 Antennae rufescentes, articulis basi pallidis, articulo basali aequaliter 

 clavato. Thorax rotundatus, dorso aequalis, olivaceo-brunneus, sericeus, 

 vittis latis tribus atro-fuscis velutinis (una centi'ali, alteris lateralibus) 

 marginem anticum hand attingentibus ornatus. Elytra elongata, de- 

 pressa, apice sinuato-truncata, angulis internis acutis, externis valde 

 productis, humeris parum prominentibus, lateribus utrinque acute 

 flexHOso-carinatis ; disco aequalia ; carina centrobasali valde prominente, 

 brevi, nuda; rufescenti-brunnea, certo visu carnea nitentia, passim punc- 

 tata et fusco maculata ; lateribus prope basin fuliginosis ; disco pone 

 medium plaga atro-fusca antice utrinque linea obliqua grisea marginata 

 ornato. Corpus subtus nigricanti-sericeum. Pedes nigricantes, tibiis 

 et tarsorum articulo primo cano annulatis. Long. 5 lin. Hab. Ve- 

 nezuela. 



