and thill- Uclatloiisliij) to the Corals. 5 



the Khizopoda, and had phiced them, in my ^ General .Mm pho- 

 logy,' in the inditterent kingdom ot" the Protista. 



Mikhicho has published the most important results of his 

 researches in his " Beitriige zur Kenntniss der Spongien," 

 which appeared in 1868 in the fourth volume of the ' Jenaische 

 Zeitschrift ' (p[). 221-240, pis. 4& 5). They relate chiefly to 

 the remarkable Gnancha h/dncn, a small calcareous sponge, 

 which is to be reckoned one of the most interesting f(jrms of 

 the whole animal kingdom; for- it forms small stockti {rormi) , 

 the constituent individuals {persona) of which belong, accord- 

 ing to their structure, to different genera, and even different 

 families, of the Calcispongias, and nevertheless grow forth from 

 one and the same root. 



Miklucho's remarkable observations on Ouancha blnnca, of 

 the accuracy of wiiich I constantly convinced myself with my 

 own eyes while in Lanzarote, induced me last winter to submit 

 to a comparative examination the numerous small calcareous 

 sponges which I had previously collected in the North Sea at 

 Heligoland, and in the Mediten*anean at Nice, Naples, and 

 Messina. Subsequently I also found some interesting small 

 calcareous sponges on stones, univalve shells, and alga?, which 

 I had collected, during my return joumey from the Canary 

 Islands, on the north-west coast of Africa, near Mogador, and 

 in the Straits of Gibraltar, near Alge^iras, and brought with 

 me well preseiwed in spirits. To this ricli material of my own 

 Avas added the calcareous sponges of the Zoological ^luseums 

 of Edinbm-gh, Berlin, Munich, and Hamburg, which MM. 

 Allman, Peters, Von Siebold, and Bolau were kind enough to 

 send me. Through M. Schmeltz, I obtained from the Godef- 

 froy Museum a number of interesting Australian calcareous 

 sponges from l^ass's Straits. My honoured friend and col- 

 league, Professor Oscar Schmidt of Gratz, was good enough 

 to send me specimens of the greater part of the calcareous 

 sponges collected by him in the Adriatic. How abundant Avas 

 the material thus placed at my command may be best learnt 

 from the fact that 1 have been able to distinguish no fewer 

 than 42 genera and 132 species among the Calcispongia}. 



I shall give exact descriptions and figures of these cal- 

 careous sponges, increased by a number of new forms which I 

 expect to have sent to me by various colleagues, in the special 

 part of my monograph of the Calcispongiae, now in course of 

 preparation. In the general part of this monograph I shall give 

 a detailed exposition of the general natural history of the Cal- 

 cispongiae, which, I hope, will advance not only the knowledge 

 of this little group, but in many respects that of the sponges 

 in general. For although the legion of the Calcispongite is 



