1S90.] MICHOSCOPICAL JOUKNAL. 33 



ment and beauty — slides from this level appear like prairies thickly 

 strewn with flowers of the most varied and brilliant colors. At 550 

 feet the deposit is much richer in species, several varieties of Aulacodis- 

 cus crux and A. sollitianus being specially abundant and beautiful. 



The culmination of the deposit seems to have occurred at about 466 

 to 4S0 feet; at this point the forms are shown in endless variety, from 

 the largest and most robust down to the most minute, many of which 

 do not exceed ^0^00 ^^ ^" inch in diameter. A peculiarly interesting 

 feature of this part of the deposit is that here are found all the charac- 

 teristic forms which occur in the artesian material from Cambridge, 

 Md., which was found 300 feet from the surface, as well as the charac- 

 teristic forms found in the Eighth street tunnel cutting at Richmond, 

 Va., which occurred at a depth of about 50 feet from the surface. At. 

 466 feet the curious and beautiful JV. disciformis is much more abun- 

 dant than in the Cambridge well. Ti'. spinosu77i is found at this point, 

 with a singular variation, as a four-sided form, an Amphitetras in fact, 

 also Tr. pentac7'inus and many beautiful species of Asteromphalus, some 

 of them similar to those found at the Island of Java. Of the many 

 novelties noted at this level a more detailed account may be given here- 

 after. Above this point a gradual dimunition of the number of species 

 takes place until at 383 feet only a few Orthosira and common cosci- 

 nodiscii are shown. Careful and scrupulously separate preparations 

 have been made from the following levels, viz : 382 feet, 390 feet, 400 

 feet, 406 feet, 415 feet, 425 feet, 466 feet, 480 feet, 500 feet, 510 feet, 

 52^ feet, 550 feet, 625 feet, 638 feet. Several of these are divided into 

 two densities and one, the 466 feet, into three, for convenience of ex- 

 amination. A good l^-inch objective gives very satisfactory views of the 

 larger forms, while for the smallest a \ or -^^ and about i ,000 linear 

 magnification are desirable. Here, then, in our own matter-of-fact and 

 prosaical Nineteenth Century we have a realization of the fancies of the 

 old Arabian story-teller who conducts his hero to a subterranean garden, 

 sparkling with gems of every variety of form and color. More fortu- 

 nate than Aladdin we are not left under ground at the mercy of the Genii, 

 but have brought up our treasures in safety and opened them out for the 

 admiration and delight of the world. 



Report upon the Postal Club Boxes. — X. 



By queen MAB. 



Box A contains several slides of unusual interest. This is due in no 

 small degree to the fullness of the descriptions which accompany them. 

 No. I is contributed by R. H. Ward, of Troy, N. Y., a Bell Hydroid, 

 an undetermined species of Campanularia, mounted in balsam, in a 

 block-tin cell, which is finished with Bell's cement. A 3-in. objective 

 is recommended for a general view, and for details, f-f • Cape Ann was 

 the source of this hydroid, and it was killed with tentacles expanded by 

 the use of picro-sulphuric acid. It has been Mr. Ward's experience 

 that this particular hydroid can be killed in a more perfect condition by 

 this reagent than by any other, though some hydroids, as Tubularia, 

 can be best killed by a saturated solution of corrosive sublimate in alco- 

 hol. If a colony of Campanularia, when brought in from a collecting 



