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BULLETIN OF THE 
PALLENOPSIS, gen. nov. 
Body slender, as in Phowichilidium, segmented. Rostrum cylindrical. Ab- 
domen slender, simple. Antenne with four joints, large and chelate. Palpi 
rudimentary, composed of a single joint. Accessory legs present in both sexes, 
ten-jointed. Legs slender, dactylus with auxiliary claws. Two very unequal 
pairs of large ocelli, 
This genus has the general appearance of a Pallene or Phoxichilidium. It is 
however very distinct from them on account of the division of the basal joint 
of the antenne into two, and in the different structure of the accessory legs ; 
and it differs from all known genera in the existence of rudimentary palpi, 
which are reduced to a single joint like the antennæ of Tanystylum or Lecytho- 
rhynchus. In all other genera, so far as I know, palpi are either quite absent or 
fully developed (apparently serving as tactile organs); and their presence or ab- 
sence is a convenient family character. Their structure in this genus shows of 
how little value this character is, save as a matter of convenience, The genus 
is exactly intermediate between the Nymphonidæ and Pallenidæ, as Scworhyn- 
chus is intermediate between the former family and the Achelide. 
The peculiar glandular duct near the middle of the fourth joints of the legs in 
the male is perhaps a character of generic significance. It has not to my knowl- 
edge been observed in any other Pycnogonid. 
Böhm has described and figured * a form from Patagonia which he identifies 
with Króyers Phorichilidium fluminense from Rio Janeiro, and which evi- 
dently should be referred to Pallenopsis. Króyer did not observe the rudi- 
mentary palpi, but the close agreement in other characters leaves little reason 
to doubt the correctness of Bóhm's identification. Neither Kroyer nor Bohm 
mentions the extra joint of the antenna, though the latter observed a “ char- 
akteristischen durch eine Linie stürkerer Haare markirten Knick,” near the 
middle of the basal joint. There can be no doubt of the presence of a distinct 
articulation ht this point in our specimens. The species described below are 
very distinct from Króyer's species ; the most striking difference is the much 
smaller size of the auxiliary claws in the former, and the non-plumose character 
of the hairs on the ambulatory legs. 
Pallenopsis forficifer, sp. nov. 
Plates IV. and V. 
Body (Fig. 15) comparatively stout, distinctly segmented. Lateral processes 
very distinct and prominent, slightly longer than the width of the body, sepa- 
rated by intervals less than their own width. The anterior pair are directed 
somewhat forwards and upwards, the posterior pair obliquely backwards like 
the branches of a V. 
* Monatsbericht der Kóniglich Preussischen Akademie der Wissenschaften zu 
Berlin, Februar, 1879, p. 180, Tafel I. Fig. 4. 
