Prof. Allman on the Hydroid Zoophytes, 36/ 



nervis omnino immersis, lineis striatis transversis interruptis 

 creberrime parallelis utrinque insculptis, costa media rubella, 

 margine revoluto, petiolo canaliculato ; paniculis brevibus, 

 petiolo 2-3-plo longioribus, pedunculo pedicellisque pubes- 

 centibus, corolla et calyce glabris, hoc dentibus ciliatis, petalis 

 lanceolatis, carina interna dense lanatis. — .Rio Guainia et Rio 

 Casiquiare in Brasilia Septentrionali (Spruce, 3536). 



The leaves are 3| inches long, IJ inch broad, on a petiole 

 3 lines in length ; the racemes are 6-9 lines long, the flowers in 

 bud IJ line long; the petals are clothed internally with dense 

 silky long hairs, springing from the prominent keel ; the stamens 

 are somewhat shorter than the petals ; the filaments are com- 

 pressed and glabrous ; the two cells of the anthers are separated,- 

 and fixed upon the margins of an obcordate connective; the 

 ovary is densely clothed with adpressed white sericeous hairs,^ 

 surmounted by a glabrous style of equal length*. 



XXXVIII. — Notes on the Hydroid Zoophytes, 

 By Prof. Allman t. 



I. Laomedea tenuis, n. sp, 



A SMALL species of Laomedea was found in August last, attached 

 to the fronds of Laminaria digit ata^ dredged from about three 

 fathoms water, ofi" the town of Stromness. It was associated 

 with L. geniculata, and, though tolerably abundant, might, from 

 its great delicacy, have been easily overlooked. 



I believe it to be an undescribed species, which may be di- 

 stinguished by the following diagnosis : — 



Stem geniculate ; polypiferous ramuli having the same diameter 

 as the stem, springing alternately from the geniculations ; the 

 entire stem and ramuli distinctly annulated ; polype-cells with 

 deeply-cleft margins; polypes very extensile, with 16 or 18 

 tentacula. Capsules medusiferous, large, cylindrical, with the 

 proximal end conical, and with the remote end broad and trun- 

 cated. 



The present species is nearly allied to L. lacerata, which it 

 resembles in its deeply-cleft polype-cells and in the form of its 

 polypes, but must be distinguished from it by its polypiferous 

 ramuli equalling the main stem in thickness, by the form of its 

 capsules, and by their contents, which are here Medusae, while 

 in L. lacerata they are sporosacs. 



* A drawing of this species, with analytical details, will be given in 

 * Contributions to Botany,' plate 22 b. 



t The species described in the present notes formed the subject of a paper 

 read by the author at the late Meeting of the British Association at Aberdeen. 



