158 Mr. G. Newport on the genus Atya^ 



ting filaments,, or, as in Chondrus, Gymnogongrus and Phyllophora 

 Stiridia (/. c. t. 16. fig. 5 d and 5 e), derive their origin from the 

 metamorphosis of the endochromes of these filaments ; 3. a form 

 of fructification which may possibly be merely a modification of 

 the former, in which the endochrome, suffering a normal hyper- 

 trophy, is not divided as a tetraspore, and presents an analogy to 

 what one meets with in certain conceptacula. However this may 

 be, one must allow that the organs in question are true spores, 

 since they are exactly like those of the species with which I have 

 compared them as regards their mode of reproduction. I ought 

 to add, that Mr. Harvey has seen something like this in the ne- 

 mathecia of Phyllophora Brodim, but he does not say whether it is 

 in the same nemathecium which incloses the tetraspores, which 

 would make a great diiference. 



XIX. — Note on the genus Atya of Leach, with descriptions of 

 four apparently new Species, in the Cabinets of the British Mu^ 

 seum. By G. Nevtport, F.R.S. &c. 



[With a Plate.] ij^ 4i^f^a^^ <0 A^ 



Fam. Macroura, Latr., Leach. 



Gen. Atya, Leach. 



When Dr. Leach described this genus of Macrourous Crusta- 

 ceans, he was acquainted with only one species. There are four 

 specimens of this in the cabinets of the British Museum, but 

 nothing whatever is known of their habits, or from whence they 

 were obtained. M. Milne Edwards, in his work on Crustacea, 

 states that Atya scabra is from the coasts of Mexico. A species 

 described in Wiegmann^s ' Archives ' for 1836, Atya mexicana, is 

 from the same country. Whether this is identical with Dr. LeacVs 

 species is not ascertained. Two new species have since been 

 added to the collection in the British Museum, one from Jamaica 

 and the other from the Philippine Islands. I have myself re- 

 ceived two others, presented to me by my friend Dr. M^William, 

 R.N., the indefatigable officer of the Niger Expedition, to whose 

 kindness I am also indebted for other valuable specimens of na- 

 tural history. These Atyas are now in our national collection. 

 One of them, a small species, is from New Zealand. This is a 

 female with an abundance of ova attached, and near the period 

 of hatching : it was found in brackish water at Apia, Upoln, 

 nine miles inland. The other species is of the size of Dr. Leach's 

 A. scabra and veiy closely resembles it, so that it may prove to 

 be only a variety of it ; but it seems to diffbr from Dr. Leaches 

 species in having the legs slightly sulcated, and the middle plate 



