INVERTEBRATA, CRYPTOGAMIA, MICROSCOPY^ ETC. 773 



the general conclusions of which we direct attention. Dealing 

 with the zoological position of the Brachiopoda, the author points 

 out that embryological investigations have shown us that the re- 

 semblances between the gills of Tunicates, Brachiopods, and Lamelli- 

 branches are adult characteristics which have been arrived at by 

 very different ways. The larvsB of the higher Brachiopods present 

 a striking resemblance to the larva of Loxosoma ; those of lower 

 forms, e. g. Lingula, have a striking similarity to the adult (and 

 especially to the fresh-water) Polyzoa ; the autlior's facts seem to 

 him to show conclusively the real resemblance between the two 

 groujis. When the adult instead of the young is examined, we 

 have incontestably to do with a solitary Bryozoon, provided with 

 a nervous system and with highly specialized sensory organs. The 

 relations of the Brachiopoda to the Vermes are much less distinct 

 than Morse imagines ; their relations to the Bryozoa are very definite. 

 As to this last, its affinities to the Veliger-form are quite appai-cnt ; 

 the velum corresponds to the lophophore, the epistoma with its 

 ganglion corresponds to the foot and the pedal ganglion ; the shell 

 and its operculum correspond to the cell and operculum of the 

 Cheilostomatous Polyzoa, and the retractor muscles are " clearly 

 homologous." The Brachioi)oda, then, may be taken to be the most 

 highly si)ecialized representatives of the Bryozoan branch, and the 

 Mollusca proper have a similar relation to the FeZ/^<?r-phylum. 



In conclusion, the author insists on the long persistence of Lingula 

 as showing that the facts of zoology absolutely forbid us to believe 

 that there must be a continuous evolution of forms owing to a 

 continuous progress upwards. 



Structure of Adeona.* — Dr. Kirchenpauer has given the first 

 detailed account of one of the most curious and but little known of 

 the Bryozoa. In 1812 Lamouroux described Adeona, and at first 

 placed it among the Isidinfe, but subsequently under Escharida), 

 which included Eschara, Bctepora, Krustensterna, Hornera, Tilesia, 

 Discopora, Dtastopora, and Celleporaria ; but as no figures of the 

 minute structure were given, it remained doubtful if Lamouroux had 

 correctly j)laced the genus. In 1819 Schweigger, who considered it 

 related to NulUpora, discussed both among tlie corals, but gave very 

 fair figures showing the zooccial cells of the Bryozoa ; the work is, 

 however, probably known to few. 



The structure of Adeona is interesting in several particulars, but 

 more especially in tlie jointed radical, upon which character the 

 genus as now described is established. This consists of calcareous 

 joints with irregular chitinous intervals, forming a flexible stem much 

 like Isis, so that it has luiturally been frequently compared to it. 

 Kirchenpauer finds, in making sections through this radical, that there 

 are fine connecting tubes passing from the chitinous jiortiou through 

 the calcareous joints. In one species the zoarium from which this root 

 springs is a calcareous f(diaccou8 growth, much resembling in shape 



* " Ueboj- d. Bryozoen-Guttung i4rftww," von Dr. KirchenpaiUT, ' Journ. Mus. 

 Godcffroy,' 1880. 



