APPENDIX. 



covered by a streal?ed, fibrous membrane, whicb, when fully developed, conceals 

 it. The younger branches, or branchlets, therefore, where this coating is 

 imperfectly grown, appear jointed, the older stems not. A branchlet, with its 

 bead-like branchleteens fringing the partition lines {dissepiments) of every 

 joint, is an exquisite microscopic object. 



Measurement. Two or four inches long, and as much in the spread of the branches. 



Fructification. Only one kind known. Tufts of naked spores formed in the middle 

 part of the branchlets, swelling them out; attached to the wJiorled branchleteens. 



Salitat. S. Catherine's Bay, Jersev: Miss Turner and Mr. Girdlestone. Exmouth: 

 Mrs. Gulson. 



It will be seen by a reference back to N. Wiggil how materially these species 

 differ in internal structure, which we call attention to because, without reference 

 to it, specimens of the two are often confounded. 



Family XIY. SQUAMAPJEJ^. 



CEUOEIA PELLITA. 



Colour. Dingy red. 



Siilstance. Tough, but rather fleshy feeling. 



Character of Frond. A scab-like incrustation spreading on the surface of rocks; 

 composed of minute densely-packed, upright, jointed threads {filaments), set in 

 gelatine. Filaments robust at the base; tapering upwards; in tufted bundles 

 below; such of them as elongate, spreading upwards in a repeatedly forked 

 manner. 



3Ieasurement. The patches indefinite. 



Fructification. Only one kind known. Tetraspores oblong, divided by zones; clavate; 



forming a branch of one of the filaments. 

 Hahitat. Sound of Jura: Rev. C. P. Miles. Cumbrae: on mussel shells (dredged), 



and on Laminaria stems; Mr. Kennedy. Miltown Malbay: Dr. Harvey. 



Probably in many other places. On rocks between tide-marks. 



The Criioria pellita. of fig. 227 has been transferred to another eenus, and 

 is now Petrocelis cruenta. This change is owing to the position and character 

 of the fruit. In Petrocelis (which, like Cnioria, is an incrustation composed 

 of jointed threads) the tetraspores are formed in the (then) swollen centre cell 

 of the threads themselves. In true Crnoria they are borne, as above described, 

 on the threads of which the frond is composed: in fact, by the transformation 

 of a branch into fruit. Scientific accounts of the Criiorias, accompanied by 

 plates, were published in the Natural History Hevieio, 1857, "Proceedings of 

 Societies," p. 201. 



CEUOEIA ADH^EEITS. 



Colour. Purplish or discolouring olive. 

 Sulstance. Tough, but rather fleshy-feeling. 



Character of Frond. A scab-like incrustation spreading on rocks and laminaria 

 stems; composed of minute densety-packed, uprig^ht, jointed threads {filaments), 

 set in gelatine. Filaments tapering to both ends; many of them quite simple; 

 a few once or twice forked upwards. 



Measurement. The patches indefinite. 



92 



