THE SMITHSONIAN INSTITUTION. 115 



^hxria, Chamo'dor^, Dasyckidus, CymojJoUa, and others, some of 

 which are West Indian, some Mediterranean, are evidence of the high 

 temixjrature of the sea round the Keys. Many of the plants obtained 

 hy me at Key West were cast up from deeper water when the south 

 wind hlew strongly, and were not seen at any other time. A visitor, 

 therefore^ in the hurricane months, would probably obtain many which 

 escaped me. Among the new species two Dclesseria', (D. involvens, 

 and D. tenuifolia) both bolonging to the hypophyllous section, are 

 specially worth notice. These were very plentiful in the beginning of 

 February, but soon disappeared, Two Bost7'ychke (B. Montagnei, and 

 B. fiUcnla, MS.) and a Caz'eweWa were found on the stems of mangroves 

 near high-water mark ; but it would extend this notice to too great a 

 ength, were I to enumerate all the forms which occur in this prolific 

 region. 



COELECTIXG AND PRESERVING SPECIMENS. 



I shall here give, for the convenience of the student, the sub- 

 stance of some directions for collecting and preserving specimens, 

 issued by the Director of the Dublin University Museum. 



Marine Algfe, as has already been stated, are found from the ex- 

 treme of high-water mark to the depth of from thirty to fifty fathoms ; 

 which latter depth is perhaps the limit in temperate latitudes ; tho, 

 majority of deep-ivater species growing at five to ten fathoms. Those 

 within the limits of the tidal influence are to be sought at low water, 

 especially the lowest water of spring tides ; for many of the rarer and 

 more interesting kinds are found only at the verge of low-water mark, 

 either along the margin of rocks partially laid bare, or, more fre- 

 quently, fringing the deep tide-pools left at low water on a flattish 

 rocky shore. The northern or shaded face of the tide-pool will be 

 found richest in red alga?, and the most sunny side in those of an 

 olive or green color. Algas which grow at a depth greater than the 

 tide exposes, are to be sought either by dredging, or by dragging 

 after a boat an iron cross armed with hooks, on all shores where those 

 contrivances can be applied ; but where the nature of the bottom, or 

 the difficulty of procuring boats, renders dredging impossible, the 

 collector must seek for deep-water species among the heaps of sea- wrack 

 thrown up by the waves. After storms seaweed sometimes forms 

 enorznous banks along the coast ; but even in ordinary tides many 

 delicate species, dislodged by the waves, float ashore, and may be 

 picked up on the beach in a perfect state. The rocky portions of a 

 coast should, therefore, be inspected at low water ; and the sandy or 

 shingly beach visited on the return of the tide. In selecting from 

 heaps we should take those specimens only that have suffered least in 

 color or texture by exposure to the air ; rejecting all bleached or half 

 melted pieces. 



Colled ors should carry with them one or two strong glass bottles 

 with wide mouths, or a hand-basket lined with japanned tin or gutta 

 percha, for the purpose of bringing home in sea-ivater the smaller and 

 more delicate kinds. This precaution is often absolutely necessary, 

 for many of the red algee rapidly decompose if exposed, even for a 



