

Mil AD.*. 



U i 



the pore*, and in many specie* are derated above the inrfaoe in the 

 form of tubular prolongation! of the canals. The ova are numerous, 

 at fint appearing like group* of minute irregularly shaped opaque 

 granules, derived from the gelatinous matter, which unite into orato 

 bodies, falling at maturity into the canal*, and are expelled by the 

 orifice*. These ora float in the water, anil exhibit spontaneous motion 

 by the rapid action of the cilia, which cover the anterior portion of 

 the body, and at length attach themselves, and then expand into the 

 forms of maturity. The currents from the orifices are best examined 

 by placing the recent animal in a shallow dish of water, and throwing 

 a little powdered chalk on the surface, the motion of which will 

 indicate the direction of the streams. For the purpose of examining 

 the skeleton, it is requisite to macerate the sponge in hot water, 

 which removes the gelatinous matter, and leaves the skeleton in a 

 state fit to be examined under a microscope. When the spicula are 

 siliceous, the animal matter may be removed by nitric acid, or by 

 combustion, as was practised by Muller (' ZooL Dan.,' t, 85), when the 

 vitreous needles will appear unaltered. 



The gelatinous lubstance of sponges is scarcely capable of conserva- 

 tion. It is usually of a ropy consistence, sliding off from the skeleton, 

 or else pressed off by the divers for sponge. It is of various colours, 

 but commonly fawn-coloured or orange-coloured; in this respect 

 resembling the gelatinous parts of Polypiaria. 



Horny Sponges with anastomosing fibres, fit for domestic use, belong 

 mostly to warm zones of the sea; sponges with calcareous spicula 

 are rather numerous on the British coasts ; and siliceous ppicula are 

 common in the sponges of most latitudes. [SPONOIAD.K.] Remains 

 of both horny and spicular sponges occur in a fossil state. 



SPO'NGIAD.E. Regarding sponges as Apolypiferous Zoophytes, 

 composed of flexible or rigid skeletons enveloped in a gelatinous moss, 

 productive of inward currents through small surface pores, and outward 

 currents through continuous canals, we may proceed to analyse the 

 large group of organic forms possessing these characters, by the 

 nature and arrangement of the skeleton, for the gelatinous part 

 (though perhaps conaervable, if due care be used) is not probably 

 capable of being examined so as to furnish distinctive and recognisable 

 characters. 



Dr. Grant pointed out the principles of thU analysis, by his observa- 

 tions on the nature and arrangement of the horny fibres, the calcareous 

 and siliceous spicula, and the formation and distribution of the pores 

 and orifices of sponges. Dr. Fleming ('Britiah Animals') gives the 

 following genera, under the family of Xpongiada: :Tethya, Ualidum- 

 dria (including Spongitta of Lamarck), Spoagia, Grantia. (Sip/ionia, 

 CkoaitHet, and raUrictUtici of Parkinson and Mautell are included in 

 Jfalichondria.) 



Blainville (' Actinologie') arranges under the head of Amorphozoa 

 AlcyontUum, Spoagia, Calcupmgia (Vrantia, Fleming), Ualitpongia, 

 SptmgiUa (fpkidatia, Lamouroux), Geodia, Codoptychiam (fossil), 

 SiptuMM, tfynucium (fosril), Scyphia, Eudea (fossil), JIalirrhoa, 

 (foaail), Ilippalimui (fossil), Onanidium (fossil), Lymrurea (fossil), 

 Ckauadopora (fossil), Tragof (fossil), itanon (fossil), lerea (fosail), 



, 



Very few of then genera, adopted from Schweigger, do 

 others, can be considered as at all sufficiently determined, 



doldfuss, and 



, ed, because the 



constituent structures of the fossil masses, on which alone they can 

 be justly founded, have, in most cases, been altogether left uncxamined. 

 Whm the modern achromatic microscope shall have been directed 

 upon them, with such perseverance as Mr. Bowerbank ('Proceedings 

 of OeoL Soc.,' 1840) has employed on the spicular structures of the 

 sponges imbedded in or constituting the nodules of flint in chalk, so 

 that the forms of the anastomosing fibres or stiffening spicula, the 

 sections and distribution of the canals, Ac., can be certainly defined, 

 great benefit will arise to this branch of zoology, and an equal 

 advantage for geology. 



I. Groups of which the Constituent Structure is known. 

 Spmgio.lia* soft, elastic, more or lew irregular in slinpe, very 

 porous, traversed by many tortuous canals which terminate at the 

 surface in distinct orifices. Substance of the skeleton cartilaginous, 

 flbrw anastomosed in all directions, without any earthy spicula. 

 Kx. > p . MMMMfa (Blainville, ' Actinologie,' pL 93, fig. 3.) 

 Calcupongia, Blainville (drantia, Fleming; LwJulia, Grant). Maw 

 rigid, or slightly elastic; of irregular form, porous, traversed by 

 Irregular canal, which terminate on the surface in distinct orifices. 

 Substance of the skeleton cartilaginous, fibres strengthened by calca- 

 reous spicula. The spicula are seldom simple, often triradiate in 

 figure. 



Kx. C. fompreua. (Montague, ' Wcrn. Trans.,' vol. ii.) 

 Altogether, Fleming and Blainville admit five species of this genus as 

 determined. They occur on the British and other northern shores. 

 I/aluptmyio, Blainville (Itatichondria, Fleming).-Mass more or 

 I rigid or friable, irregular, porous, traversed by tortuous irregular 

 canal*, which terminate at the surface in distinct orifices. Substance 

 cartilaginous, fibres strengthened by siliceous (generally fusiform or 

 cylindrical) rpicula. 



Kx. //. lapillant, Grant. (' New Edinb. Journal,' voL ii.) 

 Blainville admits fourteen specie*. Fleming, who includes in it 

 wh-water UptmgUla (Ephydalia, Lamourmix), counts eighteen 



specie*. In what manner the immense number of species of sponges 

 mentioned by Montague and Lamarck are to be distributed among 

 these three groups, which ought to be considered families rather th.-m 

 genera, does not appear. 



The remarkable siliceous sponge [SPONOIA] examined by Mr. Stutch- 

 bury of Bristol, would appear justly entitled to constitute a new genus. 



Xpongilla, Lamarck and Blaiuvillo (Kphydatia, Lamouroux). Moss 

 more or leas rigid or friable, irregular, porous, but not furnished with 

 regular orifices to internal canals. 



Ex. S. flumatUit, Linn. ; & lactulrit, Linn. For the animal nature 

 of these fresh-water sponges the argument is less complete than for 

 the marine tribes. By experiments as to the effect of light on them, 

 Mr. John Hogg (' Linn. Trans.') has endeavoured to show that they 

 are influenced by this agent in the same manner as plants are, and 

 that their green colour depends upon exposure to it. 



IL Groups depending on Characters of Surface or general Figure. 



Geodia, Lamarck. Mass fleshy, tuberous, irregular, hollow within, 

 externally incrusted by a porous envelope, which bears a series of 

 orifices in a small tubercular space. 



Ex. O. gikberota, Schweigger. (Blainville, ' Actinologie.') 



Codoplychium, Goldfuss. Mass fixed, pedicled, the upper part 

 expanded, agariciform, concave, and radiato-porose above, flat and 

 radiato-sulcate below. Substance fibrous. 



Ex. C. agaricloideum, Goldfuss. (' Petrefactenkunde,' pL 9.) From 

 the chalk of Westphalia. 



Siphonia, Parkinson. Mass polymorphous, free or fixed, ramose or 

 simple, concave or fistulous above, porous at the surface, and pene- 

 trated by anastomosing canals, which terminate in subradiating orifices 

 within the cup. 



Ex., living, 8. typum. (Blainville, ' Actinologie.,' pi. 95.) Sicily. 



Ex., fossil, & pyriformit, Goldfuss. ('Petrefactenkunde,' tab. 6, 

 fig. 7, a, 4, c, d, e.) 



AUoMB) abound in the Greensand Formation. 



Myrmecium, Goldfuss. Mass subglobular, sessile, of a clogo fibrous 

 texture, forming ramified canals which radiate from the base to the 

 circumference ; summit with a central pit 



Ex. M. liemitphericum, Qoldfuss. (' Petref.,' tab. 6.) 



Scyphia, Oken. Mass cylindrical, simple, or branched, fistulous, 

 ending in a large rounded pit, and composed entirely of a reticulated 

 (firm) tissue. 



Ex., living, S. Jittularii, Esper. (Tab. 20, fig. 2.) 



Ex., fossil, X mammillaru, Goldf. ('Petref.,' tab. 2, fig. 1.) 



Eudea, Lamouroux. Moss filiform, attenuated, subpedicellated at 

 one end, the other enlarged, rounded, with a large terminal pit; 

 surface reticulated by irregular lacuna:, minutely porous. 



Ex. K. clavata, Lamouroux. ('Gen. des Polyp.,' tab. 74, fig. 1-4.) 



JIalirrhoa, Lamouroux. Mass turbinated, nearly regular, circular, 

 or lobate ; surface porous ; a large central pit on the upper face. 



Ex. H. coitata, Lamouroux. (' Gen. des Polyp.,' pi. 78.) From the 

 Oolite of Caen. 



Jlappalimtu, Lamouroux. Moss fungiform, pediccllatcd below, 

 conically expanded with a central pit above; surface porose, and 

 irregularly excavated. 



Ex. II. fungoida, Lamouroux. (' Gen. des Polyp.,' pi. 79.) From 

 the Oolite of Caen. 



Cnemidium, Goldfuss. Mass turbinated, sessile, composed of close 

 fibres and horizontal canal*, diverging from the centre to the circum- 

 ference ; a central pit on the upper surface, cariose in the exterior, 

 and radiated at the margins. 



Ex. C. lamellotum, Qoldf. (' Petref.,' tab. 6.) 



Lymnorea, Lamouroux. Masses mammellated, finely porous and 

 reticulated, agglomerated within a common calyciform wrinkled 

 adherent base. 



Ex. L. niimmillaia, Lamouroux. (' Gen. des Polyp.,' tab. 79, fig. 2.) 

 From the Oolite of Caen. 



Clienendopora, Lamouroux. Mass conical, infuiidibuliform, external 

 surface sulcated across; internal face porose. 



Ex. C. fwngiform.ii, Lamouroux. ('Gen. des Polyp.,' pi. 75.) From 

 the Oolite of Caen. 



Tragot, Schweigger. Mass composed of dense close, coalescing 

 fibres ; surface covered by distinct scattered orifices. 



Ex. T. difforme, Ooldfuss. (' Petref.,' tab. 5, fig. 3.) 



Manon, Schweigger. Mass composed of reticulated fibres, pierced 

 on the upper face by distinct encrusted circumscribed orifices. 



Kx. M. tubulifcrum, Qoldf. (' Actinologie,' pi. 95.) From the Chalk 

 of Maastricht. 



lerea, Lamouroux. Mass ovoid, subpediculated, finely and irregu- 

 larly porous, pierced on the upper part by many orifices, the termi 

 nations of internal tubes. 



Ex. /. pyriformii, Lamouroux. (' Gen. des Polyp.,' tab. 78.) From 

 the Oolite of Caen. 



Telhium, Lamarck. Mass subglobose, tuberose, composed of a 

 cariose firm substance, strengthened by abundance of simple 

 (siliceous ?) spicula fasciculated and diverging from the centre to the 

 circumference. 



Kx. T. lyacurium, Maraigli. ('Actinologie,' pL 91, fig. 3.) 



