468 Dr. J. E. Gray on the Antilocapriclse. 



each side of the medial line there is a red band having a bright 

 golden lustre ; in the space between these bands another band 

 extends^ that projects from each side three short streaks directed 

 obliquely backwards^ and has a small spot on each side, near its 

 posterior extremity ; the band^ streaks, and spots, with the two 

 anterior protuberances, have a black hue ; the under part has a 

 silvery lustre, with a slight golden tinge, and is bounded on 

 each side by two longitudinal dark-brown bands, comprising 

 between them another of a dull-red hue : the sexual organs 

 form a transverse oval j a small process is connected with their 

 posterior margin, and their colour is pale reddish-brown; the 

 branchial df)ercula have a yellow hue^ and that of the spinners 

 is brown. 



The collection contained an adult female of this brilliant 

 Tetragnatha. 



Tribe Senoculina. 



Family Scytodid^e. 



Genus Scytodes, Latr. 



Scytodes thoracica. 



Scytodes thoracica, "^ixldk. Hist. Nat. dcs Insect. Apt. torn. i. p. 270; 



Latr. Gen. Crust, et Insect, torn. i. p. 99 ; Blackw. Spiders of Great 



Britain and Ireland, part 2. p. 380, pi. 29. fig. 272. 

 tigrina, Koch, Die Araclm. Band v. p. 87, tab. 167. fig. 398. 



One adult female of this species was included in the collection. 



LYIII. — Additional Note on the Antilocapridse. 

 By Dr. J. E. Gray, E.R.S. &c. 



After my notes on this family were written and the manuscript 

 sent to the printer, I heard that Dr. Sclater had made some 

 observations on the genus at the British-Association Meeting at 

 Nottingham. The paper is published in the last Number of 

 the Annals. I am very glad to find that Dr. Sclater agrees 

 with me in the necessity of forming the genus into a peculiar 

 family. 



Dr. Sclater has adopted Dr. SundevalPs division of the Rumi- 

 nants into two groups, according to the form of the foot; but 

 I think his change of SundevalFs term Digitigrada into Pha- 

 langigrada is to be regretted, as adding a useless synonym. 



There is no doubt that the form of the placenta is an interest- 

 ing physiological fact ; but I doubt its applicability to zoological 

 classification. It is only to be observed at one period of the 

 animaFs life, and is only known in a very few species : for ex- 

 ample, I am not aware that it is known in Antilocapra, the 



