PHOF. ALLMAN OS NiSW GEN£KA AND SPECIES OE IIYDUOIDA. 251 



her into a small cup contaiuiug a number of larv«. She worked 

 continuously till half past seven in the evening, when I left oif 

 watching. During that time she had made more than ninety 

 journeys, carrying each time a larva to the nest. During the 

 whole time not a single other ant came to the larvae. 



Again on the 7th Feb. I watched two ants in the same manner. 

 At 7 A.M. I put some larvae in the small china cups. Up to 8 no 

 ants had come to them. Soon after 8 I put two marked ants, 

 neither of them being the same as these whose movements are 

 above recorded. They were then watched until a quarter to eight 

 in the evening, during which time one of them had made twenty- 

 six journeys, carrying oft' a larva each time ; the other forty-two. 

 During this period of about eleven hours, two strange ants had 

 come to the cup at which these were working, and the same 

 number to one of the other cups. 



Kone of these ants, therefore, though they had found a large 

 number of larvae, more than they could carry in a whole day, sum- 

 moned any other to their assistance. 



Diagnoses of new G-enera and Species of Ilydroida. 

 By Professor Allman, M.D., LL.D.,E.E.S., Pres. L.S., &c. 



[Eead December 17th, 1874.] 



(Plates IX.-XXIII.) 



Some very interesting collections of Ilydroida have been recently 

 placed in my hands for determination. One of the most impor- 

 tant of these is from the Zoological Museum of the University of 

 Copenhagen, and consists exclusively of gymnoblastic forms. It 

 has been obtained from various parts of the world ; but most of 

 the species are from the Scandinavian shores. It has been put 

 into spirits, and is, for the most part, in a very good state of 

 preservation, so much so, indeed, as frequently to admit of accu- 

 rate drawings being made from the soft parts. Among the 

 Hydroids of this collection sufficiently well preserved for deter- 

 mination, are seven undescribed species, referable to six genera. 

 For the opportunity of examining it I am indebted to Professor 

 Liitken, of the Universit}^ of Copenhagen. 



Another collection, also preserved in spirits, consists entirely 

 of calyptoblastic forms, and was made in the Japaa seas by Capt. 



LINN. JOUBN. — ZOOLOGT, VOL. XII. 18 



