SIPHONOPHORA. 51 
Amongst the examples from the Volcan de Agua there are numerous smaller 
individuals which, provisionally at all events, I regard as immature females. They 
measure up to 15 millim. in length, and have as many as 58 segments; and differ 
from the type in having the rostrum narrower at the base and the head more 
constricted in front of the antenne. 
3. Siphonophora globiceps, sp. n. (Tab. V. figg. 6, 6 a.) 
2. Colour pale yellowish-white. 
Differing from the two preceding and the following species in the subspherical head, which is much more 
abruptly constricted in front of the antennal sockets, and in the shortness of the rostrum, which is much 
shorter than the head and narrower at the base than is S. cornuta, S. brevicornis, and S. meaicana. 
Antenne short and strongly incrassate distally. Number of segments 71. 
Length 21, width barely 1 millim. 
Hab. GuatTeMELA, Purula (Stoll). 
The following species I have not seen :— 
4. Siphonophora mexicana. 
Siphonophora mexicana, Humb. et Sauss. Rev. et Mag. Zool. 1869, p. 155"; Miss. Sci. Mex., Myr. 
pp- 105, 106, t. 2. figg. 7, 7a-m”. 
In the length of the rostrum, the length and shape of the antenne, and the emargination of the first tergite, 
this species seems to resemble S. brevicornis. But the typical example, which is a male, differs essentially 
from the male of S. brevicornis in its much larger size, measuring 29 millim, in length, and in possessing 
102 segments. 
Hab. Mexico, Eastern Cordillera! ?, Sierra de Agua near Orizaba ?. 
Group II. CHORDEUMOIDEA. 
Number of segments varying from 26 to 32, constant in the genera. Mouth-parts of the normal Chilognathous 
type: stipites widely separated posteriorly ; lingual plates large; promentum triangular, not always 
separated from mentum. Head not tucked under the first tergal plate, which is hollowed behind for its 
reception. Tergal plates furnished with three pairs of stout or slender sete issuing from tubercles. 
No scent-glands. No pleure. Sterna free. First, second, and fourth segments with one pair of 
legs ; third apodous; fifth and sixth with two pairs, there being seven pairs of legs in front of those of the 
seventh segment. No true phallopods ; first pair of legs of seventh segment greatly modified in male ; 
posterior pair also modified and more or fewer of the preceding or succeeding appendages as well. 
Penes perforating cox of second legs. 
Fam. CRASPEDOSOMIDA. 
Segments 30. Eyes (when present) forming a compact triangular cluster. 
Distribution. Holarctic, Mediterranean, and Sonoran Regions. 
H 2 
