770 



of Practical 



pearance greatly improved by the application 1 " Asteriad*. Fasten two or three threads 



of a very little olive oil to them, either with ! to their arms, and plunge them suddenly 



: a bit of soft leather or a brush. into boiling water for three or four minutes, 



j The best way of preparing Shells for the i according to their size, and then dry in a 



cabinet is to procure a supply of thick paste- , draught." 



board, soft enough to be easily cut with a I 



knife. Get a bookbinder to cover one side of 



it with paper of a light stone colour, and 



: when dry, to cut into strips of the uniform 



breadth of three inches, the length varying i class. Whenever they are taken from the sea 

 according to the size of the shells ; to these I they should be plunged into a vessel of cold 

 slips of card the shells are affixed with a ; fresh water, or else their curious spines will 

 little thick paste, made of gum arabic, brown drop off. Enlarge their anal opening, ex- 

 sugar, flour, and a little water. In the case tract the contents of their shell, and stuff 

 of Univalve Shells, such as the Whelk, two with cotton after applying the soap. 



ECHINODERMATA. 



Sea Urchins, and Sea Eggs, belong to this 



specimens are required to show the specie 



one lying in its natural position with its 



mouth undermost and the apex of the spire 



j pointing backwards to the right hand, the 



ENTOZOA. 

 Intestinal Parasites can only be preserved 



________________________________ __ f _______ 



i second lying in the same position, but with i in alcohol, or in Gpadby's solution ; they are 



the mouth uppermost. Some Bivalves, such j found in many animals, birds, and fishes. 

 i as the Solens or Razor-shells, may have both ' 

 f valves gummed down with their inner sur- 

 i face uppermost, and another shell of the same 

 I species in the reversed position. As it is 

 from the impressions of certain muscles on 



the interior surface, and the teeth and other 

 markings of the hinge of bivalve shells, that 

 their generic characters are chiefly drawn, 

 shells such as the Cockle may have one valve 

 fastened down to the card, whilst the other 



ZOOPHYTES AND SPONGES. 



These are a very curious class of beings, 

 whose animal nature was long a subject of 



grave dispute. The beautiful works of the 

 talente_d Dr. Johnston on these two classes 

 have given a great impulse to their investiga- 

 tion. A few species may be collected in 

 pools left by the tide, but the dredge is again 



valve is made to rest partly on the card and i the collector's main stay. A great variety 

 partly on the opposite side from the hinge ; however may be picked up in a short space of 

 in the other valve ; and in the case of a large ! time, by diligently examining the refuse of 

 shell, the lowermost valve may be rested on : the fishers' nets, lines, and boats. Every col- 

 a cradle, which may be easily fashioned out ! lector will have to contend with the pre- 

 of a piece of cork or soft wood. The scien- I judices of these hardy fellows, and bear with 



tiflc name is written or printed with the pen. 

 in the left-hand corner on the lower margin 

 of the card. All the more minute and fragile 

 shells are best preserved in glass tubes. 



RADIATA. 



In the Zoologist for 1847, page 1849., will 

 be found the following simple directions for 

 the preparation of Radiata. 



their silent, if not expressed, contempt for 

 their much-prized " rubbish ;" but a little 

 perseverance, kindness, and good humour, 

 and a few presents, will by and by win their 

 good graces. 



Zoophytes and Sponges must be steeped in 

 cold fresh water, and dried in a draught, and 

 then deposited in card trays or between sheets 

 of paper, like dried plants. 



For a List of Persons, in London or its vicinity, who can supply Zoological 

 Objects and Natural History Apparatus, see end of Introduction. 



