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THE MUSEUM. 



them to other and better authorities. 

 We shall be pleased to assist any one 

 who will put some time into this. Col- 

 lectors in Colorado and other eastern 

 Rocky Mountain states are particularly 

 desired to look for the minute Pupa's 

 Bifidaria, etc We shall be pleased 

 to exchange specimens in any line of 

 natural history for what you collect 



Among the Lower Invertebrates. 



The lower forms of life in the ocean 

 always attract the attention of natur- 

 alists, mainly because of the trouble 

 and work of getting them, and the fact 

 that so few are found in the average 

 collection. About all that are ever 

 seen are a few dried starfish and Urch- 

 ins, but many of the more delicate 

 forms must be preserved in liquid. 

 Formerly alcohol was the only medium 

 used to any extent and the result was 

 that specimens were expensive. Now 

 that formolin has come into general 

 use and the fact that it is quite inex- 

 pensive, collectors are adding many of 

 the more curious and lower forms of 

 life. For a very small amount quite a 

 large collection can now be secured. 



Among the Porifera or sponges, one 

 of the more common forms is Chalina 

 oculta. This is a bushy form, occas- 

 ionall found on piles of rocks. It is 

 transpi: t and is commonly called 

 Dead-man's lingers. It is usually 

 found where there is a considerable 

 current of clear water. If the condi- 

 tions are favorable for growth, it will 

 attain a height of two feet. The Gran 

 tia belongs to another sub- order as also 

 does Microciona proiifera, which is 

 sometimes found along Cape Cod and 

 Long Island Sound It grows in the 

 pools and tideways. When in still 

 water and on a smooth surface, it 

 forms a thin smooth sheet, but under 

 other conditions it tends to grow up- 

 right, and form branching masses a few 

 inches in height. It is of bright color 

 and produces rich effects when much 

 of it is present Cliona sulphurea be- 

 longs to another sub-order of the 



sponge family, a group which has ac- 

 customed itself to a life of borers. 

 While they do not attempt to bore in- 

 to hard rocks, they are quite destruct- 

 ive to the shells of various mollusks, 

 and even to limestone and marble. 

 This sponge penetrates and excavates 

 chambers in the shell of a mollu^k.and 

 then after causing the death of the an- 

 imal, it will entirely enclose and resorb 

 what is left of the shell. Not content 

 with this, it frequently proceeds to grow 

 around stones, or take them in until its 

 flesh is full of such ballast. Some- 

 times this form is found attached in 

 the usual manner, and when the local- 

 ity is free from stone or sand, the 

 specimen is clean and free from such 

 incumbrance Leucosolcnia belongs 

 to a class of fine tiny sponges that 

 grow in clusters. Very curios form. 

 Suberites compacta belongs to the 

 same order as Cliona and is the only 

 form in the vicinity of Cape Cod that 

 is able to live on the shifting sands. 

 The pores are so small and the struct- 

 ure so dense, that the sand cannot ob- 

 tain an entrance, while its lightness 

 keeps it from being buried. They are 

 frequently washed ashore in consider- 

 able numbers. 



Among the great Hydroid group are 

 found many interesting forms on our 

 eastern coast. Companularia is a 

 good form for illustrating. It grows 

 in small tree-like forms on the rocks. 

 Pennaria tiarella also grows in tree- 

 like masses in small colonies. This 

 specimen with Gonionemus vertens are 

 two of the most interesting of their 

 kind. As stated above the Pennaria 

 to all appearances is a small tree, and 

 has every form of one, but it is not 

 classed as a plant at all but is really an 

 animal. As positive proof of this, all 

 over its surface are small feathery 

 masses, which are in process of devel- 

 opment like a rose In due time if 

 not molested these would have fully 

 developed, and by its own action, freed 

 itself from the original stem and floated 

 off in the water a free swimming live 

 animal, so commonly called "Jelly 



